3 perldiag - various Perl diagnostics
7 These messages are classified as follows (listed in increasing order of
10 (W) A warning (optional).
11 (D) A deprecation (optional).
12 (S) A severe warning (default).
13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
15 (X) A very fatal error (nontrappable).
16 (A) An alien error message (not generated by Perl).
18 The majority of messages from the first three classifications above
19 (W, D & S) can be controlled using the C<warnings> pragma.
21 If a message can be controlled by the C<warnings> pragma, its warning
22 category is included with the classification letter in the description
25 Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
26 and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
27 to a reference to a routine that will be called on each warning instead
28 of printing it. See L<perlvar>.
30 Default warnings are always enabled unless they are explicitly disabled
31 with the C<warnings> pragma or the B<-X> switch.
33 Trappable errors may be trapped using the eval operator. See
34 L<perlfunc/eval>. In almost all cases, warnings may be selectively
35 disabled or promoted to fatal errors using the C<warnings> pragma.
38 The messages are in alphabetical order, without regard to upper or
39 lower-case. Some of these messages are generic. Spots that vary are
40 denoted with a %s or other printf-style escape. These escapes are
41 ignored by the alphabetical order, as are all characters other than
42 letters. To look up your message, just ignore anything that is not a
47 =item accept() on closed socket %s
49 (W closed) You tried to do an accept on a closed socket. Did you forget
50 to check the return value of your socket() call? See
53 =item Allocation too large: %lx
55 (X) You can't allocate more than 64K on an MS-DOS machine.
57 =item '%c' allowed only after types %s
59 (F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60 after certain types. See L<perlfunc/pack>.
62 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
64 (W ambiguous) A subroutine you have declared has the same name as a Perl
65 keyword, and you have used the name without qualification for calling
66 one or the other. Perl decided to call the builtin because the
67 subroutine is not imported.
69 To force interpretation as a subroutine call, either put an ampersand
70 before the subroutine name, or qualify the name with its package.
71 Alternatively, you can import the subroutine (or pretend that it's
72 imported with the C<use subs> pragma).
74 To silently interpret it as the Perl operator, use the C<CORE::> prefix
75 on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
76 to be an object method (see L<perlsub/"Subroutine Attributes"> or
79 =item Ambiguous range in transliteration operator
81 (F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82 all. To include a C<-> character in a transliteration, put it either
83 first or last. (In the past, C<tr/a-z-0//> was synonymous with
84 C<tr/a-y//>, which was probably not what you would have expected.)
86 =item Ambiguous use of %s resolved as %s
88 (W ambiguous)(S) You said something that may not be interpreted the way
89 you thought. Normally it's pretty easy to disambiguate it by supplying
90 a missing quote, operator, parenthesis pair or declaration.
92 =item '|' and '<' may not both be specified on command line
94 (F) An error peculiar to VMS. Perl does its own command line
95 redirection, and found that STDIN was a pipe, and that you also tried to
96 redirect STDIN using '<'. Only one STDIN stream to a customer, please.
98 =item '|' and '>' may not both be specified on command line
100 (F) An error peculiar to VMS. Perl does its own command line
101 redirection, and thinks you tried to redirect stdout both to a file and
102 into a pipe to another command. You need to choose one or the other,
103 though nothing's stopping you from piping into a program or Perl script
104 which 'splits' output into two streams, such as
106 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
113 =item Applying %s to %s will act on scalar(%s)
115 (W misc) The pattern match (C<//>), substitution (C<s///>), and
116 transliteration (C<tr///>) operators work on scalar values. If you apply
117 one of them to an array or a hash, it will convert the array or hash to
118 a scalar value -- the length of an array, or the population info of a
119 hash -- and then work on that scalar value. This is probably not what
120 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
123 =item Args must match #! line
125 (F) The setuid emulator requires that the arguments Perl was invoked
126 with match the arguments specified on the #! line. Since some systems
127 impose a one-argument limit on the #! line, try combining switches;
128 for example, turn C<-w -U> into C<-wU>.
130 =item Arg too short for msgsnd
132 (F) msgsnd() requires a string at least as long as sizeof(long).
134 =item %s argument is not a HASH or ARRAY element
136 (F) The argument to exists() must be a hash or array element, such as:
141 =item %s argument is not a HASH or ARRAY element or slice
143 (F) The argument to delete() must be either a hash or array element,
149 or a hash or array slice, such as:
151 @foo[$bar, $baz, $xyzzy]
152 @{$ref->[12]}{"susie", "queue"}
154 =item %s argument is not a subroutine name
156 (F) The argument to exists() for C<exists &sub> must be a subroutine
157 name, and not a subroutine call. C<exists &sub()> will generate this
160 =item Argument "%s" isn't numeric%s
162 (W numeric) The indicated string was fed as an argument to an operator
163 that expected a numeric value instead. If you're fortunate the message
164 will identify which operator was so unfortunate.
166 =item Argument list not closed for PerlIO layer "%s"
168 (W layer) When pushing a layer with arguments onto the Perl I/O system you
169 forgot the ) that closes the argument list. (Layers take care of transforming
170 data between external and internal representations.) Perl stopped parsing
171 the layer list at this point and did not attempt to push this layer.
172 If your program didn't explicitly request the failing operation, it may be
173 the result of the value of the environment variable PERLIO.
175 =item Array @%s missing the @ in argument %d of %s()
177 (D deprecated) Really old Perl let you omit the @ on array names in some
178 spots. This is now heavily deprecated.
180 =item assertion botched: %s
182 (P) The malloc package that comes with Perl had an internal failure.
184 =item Assertion failed: file "%s"
186 (P) A general assertion failed. The file in question must be examined.
188 =item Assignment to both a list and a scalar
190 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
191 must either both be scalars or both be lists. Otherwise Perl won't
192 know which context to supply to the right side.
194 =item A thread exited while %d threads were running
196 (W) When using threaded Perl, a thread (not necessarily the main
197 thread) exited while there were still other threads running.
198 Usually it's a good idea to first collect the return values of the
199 created threads by joining them, and only then exit from the main
200 thread. See L<threads>.
202 =item Attempt to access disallowed key '%s' in a restricted hash
204 (F) The failing code has attempted to get or set a key which is not in
205 the current set of allowed keys of a restricted hash.
207 =item Attempt to bless into a reference
209 (F) The CLASSNAME argument to the bless() operator is expected to be
210 the name of the package to bless the resulting object into. You've
211 supplied instead a reference to something: perhaps you wrote
217 bless $self, ref($proto) || $proto;
219 If you actually want to bless into the stringified version
220 of the reference supplied, you need to stringify it yourself, for
223 bless $self, "$proto";
225 =item Attempt to delete disallowed key '%s' from a restricted hash
227 (F) The failing code attempted to delete from a restricted hash a key
228 which is not in its key set.
230 =item Attempt to delete readonly key '%s' from a restricted hash
232 (F) The failing code attempted to delete a key whose value has been
233 declared readonly from a restricted hash.
235 =item Attempt to free non-arena SV: 0x%lx
237 (P internal) All SV objects are supposed to be allocated from arenas
238 that will be garbage collected on exit. An SV was discovered to be
239 outside any of those arenas.
241 =item Attempt to free nonexistent shared string
243 (P internal) Perl maintains a reference counted internal table of
244 strings to optimize the storage and access of hash keys and other
245 strings. This indicates someone tried to decrement the reference count
246 of a string that can no longer be found in the table.
248 =item Attempt to free temp prematurely
250 (W debugging) Mortalized values are supposed to be freed by the
251 free_tmps() routine. This indicates that something else is freeing the
252 SV before the free_tmps() routine gets a chance, which means that the
253 free_tmps() routine will be freeing an unreferenced scalar when it does
256 =item Attempt to free unreferenced glob pointers
258 (P internal) The reference counts got screwed up on symbol aliases.
260 =item Attempt to free unreferenced scalar
262 (W internal) Perl went to decrement the reference count of a scalar to
263 see if it would go to 0, and discovered that it had already gone to 0
264 earlier, and should have been freed, and in fact, probably was freed.
265 This could indicate that SvREFCNT_dec() was called too many times, or
266 that SvREFCNT_inc() was called too few times, or that the SV was
267 mortalized when it shouldn't have been, or that memory has been
270 =item Attempt to join self
272 (F) You tried to join a thread from within itself, which is an
273 impossible task. You may be joining the wrong thread, or you may need
274 to move the join() to some other thread.
276 =item Attempt to pack pointer to temporary value
278 (W pack) You tried to pass a temporary value (like the result of a
279 function, or a computed expression) to the "p" pack() template. This
280 means the result contains a pointer to a location that could become
281 invalid anytime, even before the end of the current statement. Use
282 literals or global values as arguments to the "p" pack() template to
285 =item Attempt to use reference as lvalue in substr
287 (W substr) You supplied a reference as the first argument to substr()
288 used as an lvalue, which is pretty strange. Perhaps you forgot to
289 dereference it first. See L<perlfunc/substr>.
291 =item Bad arg length for %s, is %d, should be %s
293 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
294 or shmctl(). In C parlance, the correct sizes are, respectively,
295 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
296 S<sizeof(struct shmid_ds *)>.
298 =item Bad evalled substitution pattern
300 (F) You've used the C</e> switch to evaluate the replacement for a
301 substitution, but perl found a syntax error in the code to evaluate,
302 most likely an unexpected right brace '}'.
304 =item Bad filehandle: %s
306 (F) A symbol was passed to something wanting a filehandle, but the
307 symbol has no filehandle associated with it. Perhaps you didn't do an
308 open(), or did it in another package.
310 =item Bad free() ignored
312 (S malloc) An internal routine called free() on something that had never
313 been malloc()ed in the first place. Mandatory, but can be disabled by
314 setting environment variable C<PERL_BADFREE> to 0.
316 This message can be seen quite often with DB_File on systems with "hard"
317 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
318 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
322 (P) One of the internal hash routines was passed a null HV pointer.
324 =item Badly placed ()'s
326 (A) You've accidentally run your script through B<csh> instead
327 of Perl. Check the #! line, or manually feed your script into
330 =item Bad name after %s::
332 (F) You started to name a symbol by using a package prefix, and then
333 didn't finish the symbol. In particular, you can't interpolate outside
342 $sym = "mypack::$var";
344 =item Bad realloc() ignored
346 (S malloc) An internal routine called realloc() on something that had
347 never been malloc()ed in the first place. Mandatory, but can be disabled
348 by setting environment variable C<PERL_BADFREE> to 1.
350 =item Bad symbol for array
352 (P) An internal request asked to add an array entry to something that
353 wasn't a symbol table entry.
355 =item Bad symbol for filehandle
357 (P) An internal request asked to add a filehandle entry to something
358 that wasn't a symbol table entry.
360 =item Bad symbol for hash
362 (P) An internal request asked to add a hash entry to something that
363 wasn't a symbol table entry.
365 =item Bareword found in conditional
367 (W bareword) The compiler found a bareword where it expected a
368 conditional, which often indicates that an || or && was parsed as part
369 of the last argument of the previous construct, for example:
373 It may also indicate a misspelled constant that has been interpreted as
376 use constant TYPO => 1;
377 if (TYOP) { print "foo" }
379 The C<strict> pragma is useful in avoiding such errors.
381 =item Bareword "%s" not allowed while "strict subs" in use
383 (F) With "strict subs" in use, a bareword is only allowed as a
384 subroutine identifier, in curly brackets or to the left of the "=>"
385 symbol. Perhaps you need to predeclare a subroutine?
387 =item Bareword "%s" refers to nonexistent package
389 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
390 compiler saw no other uses of that namespace before that point. Perhaps
391 you need to predeclare a package?
393 =item BEGIN failed--compilation aborted
395 (F) An untrapped exception was raised while executing a BEGIN
396 subroutine. Compilation stops immediately and the interpreter is
399 =item BEGIN not safe after errors--compilation aborted
401 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
402 implies a C<BEGIN {}>) after one or more compilation errors had already
403 occurred. Since the intended environment for the C<BEGIN {}> could not
404 be guaranteed (due to the errors), and since subsequent code likely
405 depends on its correct operation, Perl just gave up.
407 =item \1 better written as $1
409 (W syntax) Outside of patterns, backreferences live on as variables.
410 The use of backslashes is grandfathered on the right-hand side of a
411 substitution, but stylistically it's better to use the variable form
412 because other Perl programmers will expect it, and it works better if
413 there are more than 9 backreferences.
415 =item Binary number > 0b11111111111111111111111111111111 non-portable
417 (W portable) The binary number you specified is larger than 2**32-1
418 (4294967295) and therefore non-portable between systems. See
419 L<perlport> for more on portability concerns.
421 =item bind() on closed socket %s
423 (W closed) You tried to do a bind on a closed socket. Did you forget to
424 check the return value of your socket() call? See L<perlfunc/bind>.
426 =item binmode() on closed filehandle %s
428 (W unopened) You tried binmode() on a filehandle that was never opened.
429 Check you control flow and number of arguments.
431 =item Bit vector size > 32 non-portable
433 (W portable) Using bit vector sizes larger than 32 is non-portable.
435 =item Bizarre copy of %s in %s
437 (P) Perl detected an attempt to copy an internal value that is not
440 =item Buffer overflow in prime_env_iter: %s
442 (W internal) A warning peculiar to VMS. While Perl was preparing to
443 iterate over %ENV, it encountered a logical name or symbol definition
444 which was too long, so it was truncated to the string shown.
446 =item Callback called exit
448 (F) A subroutine invoked from an external package via call_sv()
449 exited by calling exit.
451 =item %s() called too early to check prototype
453 (W prototype) You've called a function that has a prototype before the
454 parser saw a definition or declaration for it, and Perl could not check
455 that the call conforms to the prototype. You need to either add an
456 early prototype declaration for the subroutine in question, or move the
457 subroutine definition ahead of the call to get proper prototype
458 checking. Alternatively, if you are certain that you're calling the
459 function correctly, you may put an ampersand before the name to avoid
460 the warning. See L<perlsub>.
462 =item Cannot compress integer in pack
464 (F) An argument to pack("w",...) was too large to compress. The BER
465 compressed integer format can only be used with positive integers, and you
466 attempted to compress Infinity or a very large number (> 1e308).
467 See L<perlfunc/pack>.
469 =item Cannot compress negative numbers in pack
471 (F) An argument to pack("w",...) was negative. The BER compressed integer
472 format can only be used with positive integers. See L<perlfunc/pack>.
474 =item Can only compress unsigned integers in pack
476 (F) An argument to pack("w",...) was not an integer. The BER compressed
477 integer format can only be used with positive integers, and you attempted
478 to compress something else. See L<perlfunc/pack>.
480 =item Can't bless non-reference value
482 (F) Only hard references may be blessed. This is how Perl "enforces"
483 encapsulation of objects. See L<perlobj>.
485 =item Can't call method "%s" in empty package "%s"
487 (F) You called a method correctly, and it correctly indicated a package
488 functioning as a class, but that package doesn't have ANYTHING defined
489 in it, let alone methods. See L<perlobj>.
491 =item Can't call method "%s" on an undefined value
493 (F) You used the syntax of a method call, but the slot filled by the
494 object reference or package name contains an undefined value. Something
495 like this will reproduce the error:
498 process $BADREF 1,2,3;
499 $BADREF->process(1,2,3);
501 =item Can't call method "%s" on unblessed reference
503 (F) A method call must know in what package it's supposed to run. It
504 ordinarily finds this out from the object reference you supply, but you
505 didn't supply an object reference in this case. A reference isn't an
506 object reference until it has been blessed. See L<perlobj>.
508 =item Can't call method "%s" without a package or object reference
510 (F) You used the syntax of a method call, but the slot filled by the
511 object reference or package name contains an expression that returns a
512 defined value which is neither an object reference nor a package name.
513 Something like this will reproduce the error:
516 process $BADREF 1,2,3;
517 $BADREF->process(1,2,3);
519 =item Can't chdir to %s
521 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
522 that you can chdir to, possibly because it doesn't exist.
524 =item Can't check filesystem of script "%s" for nosuid
526 (P) For some reason you can't check the filesystem of the script for
529 =item Can't coerce array into hash
531 (F) You used an array where a hash was expected, but the array has no
532 information on how to map from keys to array indices. You can do that
533 only with arrays that have a hash reference at index 0.
535 =item Can't coerce %s to integer in %s
537 (F) Certain types of SVs, in particular real symbol table entries
538 (typeglobs), can't be forced to stop being what they are. So you can't
548 but then $foo no longer contains a glob.
550 =item Can't coerce %s to number in %s
552 (F) Certain types of SVs, in particular real symbol table entries
553 (typeglobs), can't be forced to stop being what they are.
555 =item Can't coerce %s to string in %s
557 (F) Certain types of SVs, in particular real symbol table entries
558 (typeglobs), can't be forced to stop being what they are.
560 =item Can't create pipe mailbox
562 (P) An error peculiar to VMS. The process is suffering from exhausted
563 quotas or other plumbing problems.
565 =item Can't declare class for non-scalar %s in "%s"
567 (F) Currently, only scalar variables can be declared with a specific
568 class qualifier in a "my" or "our" declaration. The semantics may be
569 extended for other types of variables in future.
571 =item Can't declare %s in "%s"
573 (F) Only scalar, array, and hash variables may be declared as "my" or
574 "our" variables. They must have ordinary identifiers as names.
576 =item Can't do inplace edit: %s is not a regular file
578 (S inplace) You tried to use the B<-i> switch on a special file, such as
579 a file in /dev, or a FIFO. The file was ignored.
581 =item Can't do inplace edit on %s: %s
583 (S inplace) The creation of the new file failed for the indicated
586 =item Can't do inplace edit without backup
588 (F) You're on a system such as MS-DOS that gets confused if you try
589 reading from a deleted (but still opened) file. You have to say
590 C<-i.bak>, or some such.
592 =item Can't do inplace edit: %s would not be unique
594 (S inplace) Your filesystem does not support filenames longer than 14
595 characters and Perl was unable to create a unique filename during
596 inplace editing with the B<-i> switch. The file was ignored.
598 =item Can't do {n,m} with n > m in regex; marked by <-- HERE in m/%s/
600 (F) Minima must be less than or equal to maxima. If you really want your
601 regexp to match something 0 times, just put {0}. The <-- HERE shows in the
602 regular expression about where the problem was discovered. See L<perlre>.
604 =item Can't do setegid!
606 (P) The setegid() call failed for some reason in the setuid emulator of
609 =item Can't do seteuid!
611 (P) The setuid emulator of suidperl failed for some reason.
613 =item Can't do setuid
615 (F) This typically means that ordinary perl tried to exec suidperl to do
616 setuid emulation, but couldn't exec it. It looks for a name of the form
617 sperl5.000 in the same directory that the perl executable resides under
618 the name perl5.000, typically /usr/local/bin on Unix machines. If the
619 file is there, check the execute permissions. If it isn't, ask your
620 sysadmin why he and/or she removed it.
622 =item Can't do waitpid with flags
624 (F) This machine doesn't have either waitpid() or wait4(), so only
625 waitpid() without flags is emulated.
627 =item Can't emulate -%s on #! line
629 (F) The #! line specifies a switch that doesn't make sense at this
630 point. For example, it'd be kind of silly to put a B<-x> on the #!
633 =item Can't %s %s-endian %ss on this platform
635 (F) Your platform's byte-order is neither big-endian nor little-endian,
636 or it has a very strange pointer size. Packing and unpacking big- or
637 little-endian floating point values and pointers may not be possible.
638 See L<perlfunc/pack>.
640 =item Can't exec "%s": %s
642 (W exec) A system(), exec(), or piped open call could not execute the
643 named program for the indicated reason. Typical reasons include: the
644 permissions were wrong on the file, the file wasn't found in
645 C<$ENV{PATH}>, the executable in question was compiled for another
646 architecture, or the #! line in a script points to an interpreter that
647 can't be run for similar reasons. (Or maybe your system doesn't support
652 (F) Perl was trying to execute the indicated program for you because
653 that's what the #! line said. If that's not what you wanted, you may
654 need to mention "perl" on the #! line somewhere.
656 =item Can't execute %s
658 (F) You used the B<-S> switch, but the copies of the script to execute
659 found in the PATH did not have correct permissions.
661 =item Can't find an opnumber for "%s"
663 (F) A string of a form C<CORE::word> was given to prototype(), but there
664 is no builtin with the name C<word>.
666 =item Can't find %s character property "%s"
668 (F) You used C<\p{}> or C<\P{}> but the character property by that name
669 could not be found. Maybe you misspelled the name of the property
670 (remember that the names of character properties consist only of
671 alphanumeric characters), or maybe you forgot the C<Is> or C<In> prefix?
673 =item Can't find label %s
675 (F) You said to goto a label that isn't mentioned anywhere that it's
676 possible for us to go to. See L<perlfunc/goto>.
678 =item Can't find %s on PATH
680 (F) You used the B<-S> switch, but the script to execute could not be
683 =item Can't find %s on PATH, '.' not in PATH
685 (F) You used the B<-S> switch, but the script to execute could not be
686 found in the PATH, or at least not with the correct permissions. The
687 script exists in the current directory, but PATH prohibits running it.
689 =item Can't find %s property definition %s
691 (F) You may have tried to use C<\p> which means a Unicode property (for
692 example C<\p{Lu}> is all uppercase letters). If you did mean to use a
693 Unicode property, see L<perlunicode> for the list of known properties.
694 If you didn't mean to use a Unicode property, escape the C<\p>, either
695 by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, until
698 =item Can't find string terminator %s anywhere before EOF
700 (F) Perl strings can stretch over multiple lines. This message means
701 that the closing delimiter was omitted. Because bracketed quotes count
702 nesting levels, the following is missing its final parenthesis:
704 print q(The character '(' starts a side comment.);
706 If you're getting this error from a here-document, you may have included
707 unseen whitespace before or after your closing tag. A good programmer's
708 editor will have a way to help you find these characters.
712 (F) A fatal error occurred while trying to fork while opening a
715 =item Can't get filespec - stale stat buffer?
717 (S) A warning peculiar to VMS. This arises because of the difference
718 between access checks under VMS and under the Unix model Perl assumes.
719 Under VMS, access checks are done by filename, rather than by bits in
720 the stat buffer, so that ACLs and other protections can be taken into
721 account. Unfortunately, Perl assumes that the stat buffer contains all
722 the necessary information, and passes it, instead of the filespec, to
723 the access checking routine. It will try to retrieve the filespec using
724 the device name and FID present in the stat buffer, but this works only
725 if you haven't made a subsequent call to the CRTL stat() routine,
726 because the device name is overwritten with each call. If this warning
727 appears, the name lookup failed, and the access checking routine gave up
728 and returned FALSE, just to be conservative. (Note: The access checking
729 routine knows about the Perl C<stat> operator and file tests, so you
730 shouldn't ever see this warning in response to a Perl command; it arises
731 only if some internal code takes stat buffers lightly.)
733 =item Can't get pipe mailbox device name
735 (P) An error peculiar to VMS. After creating a mailbox to act as a
736 pipe, Perl can't retrieve its name for later use.
738 =item Can't get SYSGEN parameter value for MAXBUF
740 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
741 mailbox buffers to be, and didn't get an answer.
743 =item Can't "goto" into the middle of a foreach loop
745 (F) A "goto" statement was executed to jump into the middle of a foreach
746 loop. You can't get there from here. See L<perlfunc/goto>.
748 =item Can't "goto" out of a pseudo block
750 (F) A "goto" statement was executed to jump out of what might look like
751 a block, except that it isn't a proper block. This usually occurs if
752 you tried to jump out of a sort() block or subroutine, which is a no-no.
753 See L<perlfunc/goto>.
755 =item Can't goto subroutine from an eval-string
757 (F) The "goto subroutine" call can't be used to jump out of an eval
758 "string". (You can use it to jump out of an eval {BLOCK}, but you
759 probably don't want to.)
761 =item Can't goto subroutine outside a subroutine
763 (F) The deeply magical "goto subroutine" call can only replace one
764 subroutine call for another. It can't manufacture one out of whole
765 cloth. In general you should be calling it out of only an AUTOLOAD
766 routine anyway. See L<perlfunc/goto>.
768 =item Can't ignore signal CHLD, forcing to default
770 (W signal) Perl has detected that it is being run with the SIGCHLD
771 signal (sometimes known as SIGCLD) disabled. Since disabling this
772 signal will interfere with proper determination of exit status of child
773 processes, Perl has reset the signal to its default value. This
774 situation typically indicates that the parent program under which Perl
775 may be running (e.g. cron) is being very careless.
777 =item Can't "last" outside a loop block
779 (F) A "last" statement was executed to break out of the current block,
780 except that there's this itty bitty problem called there isn't a current
781 block. Note that an "if" or "else" block doesn't count as a "loopish"
782 block, as doesn't a block given to sort(), map() or grep(). You can
783 usually double the curlies to get the same effect though, because the
784 inner curlies will be considered a block that loops once. See
787 =item Can't localize lexical variable %s
789 (F) You used local on a variable name that was previously declared as a
790 lexical variable using "my". This is not allowed. If you want to
791 localize a package variable of the same name, qualify it with the
794 =item Can't localize through a reference
796 (F) You said something like C<local $$ref>, which Perl can't currently
797 handle, because when it goes to restore the old value of whatever $ref
798 pointed to after the scope of the local() is finished, it can't be sure
799 that $ref will still be a reference.
801 =item Can't locate %s
803 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be
804 found. Perl looks for the file in all the locations mentioned in @INC,
805 unless the file name included the full path to the file. Perhaps you
806 need to set the PERL5LIB or PERL5OPT environment variable to say where
807 the extra library is, or maybe the script needs to add the library name
808 to @INC. Or maybe you just misspelled the name of the file. See
809 L<perlfunc/require> and L<lib>.
811 =item Can't locate auto/%s.al in @INC
813 (F) A function (or method) was called in a package which allows
814 autoload, but there is no function to autoload. Most probable causes
815 are a misprint in a function/method name or a failure to C<AutoSplit>
816 the file, say, by doing C<make install>.
818 =item Can't locate object method "%s" via package "%s"
820 (F) You called a method correctly, and it correctly indicated a package
821 functioning as a class, but that package doesn't define that particular
822 method, nor does any of its base classes. See L<perlobj>.
824 =item Can't locate package %s for @%s::ISA
826 (W syntax) The @ISA array contained the name of another package that
827 doesn't seem to exist.
829 =item Can't locate PerlIO%s
831 (F) You tried to use in open() a PerlIO layer that does not exist,
832 e.g. open(FH, ">:nosuchlayer", "somefile").
834 =item Can't make list assignment to \%ENV on this system
836 (F) List assignment to %ENV is not supported on some systems, notably
839 =item Can't modify %s in %s
841 (F) You aren't allowed to assign to the item indicated, or otherwise try
842 to change it, such as with an auto-increment.
844 =item Can't modify nonexistent substring
846 (P) The internal routine that does assignment to a substr() was handed
849 =item Can't modify non-lvalue subroutine call
851 (F) Subroutines meant to be used in lvalue context should be declared as
852 such, see L<perlsub/"Lvalue subroutines">.
854 =item Can't msgrcv to read-only var
856 (F) The target of a msgrcv must be modifiable to be used as a receive
859 =item Can't "next" outside a loop block
861 (F) A "next" statement was executed to reiterate the current block, but
862 there isn't a current block. Note that an "if" or "else" block doesn't
863 count as a "loopish" block, as doesn't a block given to sort(), map() or
864 grep(). You can usually double the curlies to get the same effect
865 though, because the inner curlies will be considered a block that loops
866 once. See L<perlfunc/next>.
868 =item Can't open %s: %s
870 (S inplace) The implicit opening of a file through use of the C<< <> >>
871 filehandle, either implicitly under the C<-n> or C<-p> command-line
872 switches, or explicitly, failed for the indicated reason. Usually this
873 is because you don't have read permission for a file which you named on
876 =item Can't open a reference
878 (W io) You tried to open a scalar reference for reading or writing,
879 using the 3-arg open() syntax :
883 but your version of perl is compiled without perlio, and this form of
884 open is not supported.
886 =item Can't open bidirectional pipe
888 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
889 You can try any of several modules in the Perl library to do this, such
890 as IPC::Open2. Alternately, direct the pipe's output to a file using
891 ">", and then read it in under a different file handle.
893 =item Can't open error file %s as stderr
895 (F) An error peculiar to VMS. Perl does its own command line
896 redirection, and couldn't open the file specified after '2>' or '2>>' on
897 the command line for writing.
899 =item Can't open input file %s as stdin
901 (F) An error peculiar to VMS. Perl does its own command line
902 redirection, and couldn't open the file specified after '<' on the
903 command line for reading.
905 =item Can't open output file %s as stdout
907 (F) An error peculiar to VMS. Perl does its own command line
908 redirection, and couldn't open the file specified after '>' or '>>' on
909 the command line for writing.
911 =item Can't open output pipe (name: %s)
913 (P) An error peculiar to VMS. Perl does its own command line
914 redirection, and couldn't open the pipe into which to send data destined
917 =item Can't open perl script%s
919 (F) The script you specified can't be opened for the indicated reason.
921 =item Can't read CRTL environ
923 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
924 from the CRTL's internal environment array and discovered the array was
925 missing. You need to figure out where your CRTL misplaced its environ
926 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
929 =item Can't redefine active sort subroutine %s
931 (F) Perl optimizes the internal handling of sort subroutines and keeps
932 pointers into them. You tried to redefine one such sort subroutine when
933 it was currently active, which is not allowed. If you really want to do
934 this, you should write C<sort { &func } @x> instead of C<sort func @x>.
936 =item Can't "redo" outside a loop block
938 (F) A "redo" statement was executed to restart the current block, but
939 there isn't a current block. Note that an "if" or "else" block doesn't
940 count as a "loopish" block, as doesn't a block given to sort(), map()
941 or grep(). You can usually double the curlies to get the same effect
942 though, because the inner curlies will be considered a block that
943 loops once. See L<perlfunc/redo>.
945 =item Can't remove %s: %s, skipping file
947 (S inplace) You requested an inplace edit without creating a backup
948 file. Perl was unable to remove the original file to replace it with
949 the modified file. The file was left unmodified.
951 =item Can't rename %s to %s: %s, skipping file
953 (S inplace) The rename done by the B<-i> switch failed for some reason,
954 probably because you don't have write permission to the directory.
956 =item Can't reopen input pipe (name: %s) in binary mode
958 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
959 to reopen it to accept binary data. Alas, it failed.
961 =item Can't resolve method `%s' overloading `%s' in package `%s'
963 (F|P) Error resolving overloading specified by a method name (as opposed
964 to a subroutine reference): no such method callable via the package. If
965 method name is C<???>, this is an internal error.
967 =item Can't reswap uid and euid
969 (P) The setreuid() call failed for some reason in the setuid emulator of
972 =item Can't return %s from lvalue subroutine
974 (F) Perl detected an attempt to return illegal lvalues (such as
975 temporary or readonly values) from a subroutine used as an lvalue. This
978 =item Can't return outside a subroutine
980 (F) The return statement was executed in mainline code, that is, where
981 there was no subroutine call to return out of. See L<perlsub>.
983 =item Can't return %s to lvalue scalar context
985 (F) You tried to return a complete array or hash from an lvalue subroutine,
986 but you called the subroutine in a way that made Perl think you meant
987 to return only one value. You probably meant to write parentheses around
988 the call to the subroutine, which tell Perl that the call should be in
991 =item Can't stat script "%s"
993 (P) For some reason you can't fstat() the script even though you have it
994 open already. Bizarre.
996 =item Can't swap uid and euid
998 (P) The setreuid() call failed for some reason in the setuid emulator of
1001 =item Can't take log of %g
1003 (F) For ordinary real numbers, you can't take the logarithm of a
1004 negative number or zero. There's a Math::Complex package that comes
1005 standard with Perl, though, if you really want to do that for the
1008 =item Can't take sqrt of %g
1010 (F) For ordinary real numbers, you can't take the square root of a
1011 negative number. There's a Math::Complex package that comes standard
1012 with Perl, though, if you really want to do that.
1014 =item Can't undef active subroutine
1016 (F) You can't undefine a routine that's currently running. You can,
1017 however, redefine it while it's running, and you can even undef the
1018 redefined subroutine while the old routine is running. Go figure.
1022 (F) You tried to unshift an "unreal" array that can't be unshifted, such
1023 as the main Perl stack.
1025 =item Can't upgrade that kind of scalar
1027 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1028 into a more specialized kind of SV. The top several SV types are so
1029 specialized, however, that they cannot be interconverted. This message
1030 indicates that such a conversion was attempted.
1032 =item Can't upgrade to undef
1034 (P) The undefined SV is the bottom of the totem pole, in the scheme of
1035 upgradability. Upgrading to undef indicates an error in the code
1038 =item Can't use anonymous symbol table for method lookup
1040 (F) The internal routine that does method lookup was handed a symbol
1041 table that doesn't have a name. Symbol tables can become anonymous
1042 for example by undefining stashes: C<undef %Some::Package::>.
1044 =item Can't use an undefined value as %s reference
1046 (F) A value used as either a hard reference or a symbolic reference must
1047 be a defined value. This helps to delurk some insidious errors.
1049 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1051 (F) Only hard references are allowed by "strict refs". Symbolic
1052 references are disallowed. See L<perlref>.
1054 =item Can't use %! because Errno.pm is not available
1056 (F) The first time the %! hash is used, perl automatically loads the
1057 Errno.pm module. The Errno module is expected to tie the %! hash to
1058 provide symbolic names for C<$!> errno values.
1060 =item Can't use both '<' and '>' after type '%c' in %s
1062 (F) A type cannot be forced to have both big-endian and little-endian
1063 byte-order at the same time, so this combination of modifiers is not
1064 allowed. See L<perlfunc/pack>.
1066 =item Can't use %s for loop variable
1068 (F) Only a simple scalar variable may be used as a loop variable on a
1071 =item Can't use global %s in "my"
1073 (F) You tried to declare a magical variable as a lexical variable. This
1074 is not allowed, because the magic can be tied to only one location
1075 (namely the global variable) and it would be incredibly confusing to
1076 have variables in your program that looked like magical variables but
1079 =item Can't use "my %s" in sort comparison
1081 (F) The global variables $a and $b are reserved for sort comparisons.
1082 You mentioned $a or $b in the same line as the <=> or cmp operator,
1083 and the variable had earlier been declared as a lexical variable.
1084 Either qualify the sort variable with the package name, or rename the
1087 =item Can't use %s ref as %s ref
1089 (F) You've mixed up your reference types. You have to dereference a
1090 reference of the type needed. You can use the ref() function to
1091 test the type of the reference, if need be.
1093 =item Can't use string ("%s") as %s ref while "strict refs" in use
1095 (F) Only hard references are allowed by "strict refs". Symbolic
1096 references are disallowed. See L<perlref>.
1098 =item Can't use subscript on %s
1100 (F) The compiler tried to interpret a bracketed expression as a
1101 subscript. But to the left of the brackets was an expression that
1102 didn't look like an array reference, or anything else subscriptable.
1104 =item Can't use \%c to mean $%c in expression
1106 (W syntax) In an ordinary expression, backslash is a unary operator that
1107 creates a reference to its argument. The use of backslash to indicate a
1108 backreference to a matched substring is valid only as part of a regular
1109 expression pattern. Trying to do this in ordinary Perl code produces a
1110 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1113 =item Can't weaken a nonreference
1115 (F) You attempted to weaken something that was not a reference. Only
1116 references can be weakened.
1118 =item Can't x= to read-only value
1120 (F) You tried to repeat a constant value (often the undefined value)
1121 with an assignment operator, which implies modifying the value itself.
1122 Perhaps you need to copy the value to a temporary, and repeat that.
1124 =item Character in "C" format wrapped in pack
1130 where $x is either less than 0 or more than 255; the C<"C"> format is
1131 only for encoding native operating system characters (ASCII, EBCDIC,
1132 and so on) and not for Unicode characters, so Perl behaved as if you meant
1136 If you actually want to pack Unicode codepoints, use the C<"U"> format
1139 =item Character in "c" format wrapped in pack
1145 where $x is either less than -128 or more than 127; the C<"c"> format
1146 is only for encoding native operating system characters (ASCII, EBCDIC,
1147 and so on) and not for Unicode characters, so Perl behaved as if you meant
1149 pack("c", $x & 255);
1151 If you actually want to pack Unicode codepoints, use the C<"U"> format
1154 =item close() on unopened filehandle %s
1156 (W unopened) You tried to close a filehandle that was never opened.
1158 =item Code missing after '/'
1160 (F) You had a (sub-)template that ends with a '/'. There must be another
1161 template code following the slash. See L<perlfunc/pack>.
1163 =item %s: Command not found
1165 (A) You've accidentally run your script through B<csh> instead of Perl.
1166 Check the #! line, or manually feed your script into Perl yourself.
1168 =item Compilation failed in require
1170 (F) Perl could not compile a file specified in a C<require> statement.
1171 Perl uses this generic message when none of the errors that it
1172 encountered were severe enough to halt compilation immediately.
1174 =item Complex regular subexpression recursion limit (%d) exceeded
1176 (W regexp) The regular expression engine uses recursion in complex
1177 situations where back-tracking is required. Recursion depth is limited
1178 to 32766, or perhaps less in architectures where the stack cannot grow
1179 arbitrarily. ("Simple" and "medium" situations are handled without
1180 recursion and are not subject to a limit.) Try shortening the string
1181 under examination; looping in Perl code (e.g. with C<while>) rather than
1182 in the regular expression engine; or rewriting the regular expression so
1183 that it is simpler or backtracks less. (See L<perlfaq2> for information
1184 on I<Mastering Regular Expressions>.)
1186 =item cond_broadcast() called on unlocked variable
1188 (W threads) Within a thread-enabled program, you tried to call
1189 cond_broadcast() on a variable which wasn't locked. The cond_broadcast()
1190 function is used to wake up another thread that is waiting in a
1191 cond_wait(). To ensure that the signal isn't sent before the other thread
1192 has a chance to enter the wait, it is usual for the signaling thread to
1193 first wait for a lock on variable. This lock attempt will only succeed
1194 after the other thread has entered cond_wait() and thus relinquished the
1197 =item cond_signal() called on unlocked variable
1199 (W threads) Within a thread-enabled program, you tried to call
1200 cond_signal() on a variable which wasn't locked. The cond_signal()
1201 function is used to wake up another thread that is waiting in a
1202 cond_wait(). To ensure that the signal isn't sent before the other thread
1203 has a chance to enter the wait, it is usual for the signaling thread to
1204 first wait for a lock on variable. This lock attempt will only succeed
1205 after the other thread has entered cond_wait() and thus relinquished the
1208 =item connect() on closed socket %s
1210 (W closed) You tried to do a connect on a closed socket. Did you forget
1211 to check the return value of your socket() call? See
1212 L<perlfunc/connect>.
1214 =item Constant(%s)%s: %s
1216 (F) The parser found inconsistencies either while attempting to define
1217 an overloaded constant, or when trying to find the character name
1218 specified in the C<\N{...}> escape. Perhaps you forgot to load the
1219 corresponding C<overload> or C<charnames> pragma? See L<charnames> and
1222 =item Constant is not %s reference
1224 (F) A constant value (perhaps declared using the C<use constant> pragma)
1225 is being dereferenced, but it amounts to the wrong type of reference.
1226 The message indicates the type of reference that was expected. This
1227 usually indicates a syntax error in dereferencing the constant value.
1228 See L<perlsub/"Constant Functions"> and L<constant>.
1230 =item Constant subroutine %s redefined
1232 (S) You redefined a subroutine which had previously been
1233 eligible for inlining. See L<perlsub/"Constant Functions"> for
1234 commentary and workarounds.
1236 =item Constant subroutine %s undefined
1238 (W misc) You undefined a subroutine which had previously been eligible
1239 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1242 =item Copy method did not return a reference
1244 (F) The method which overloads "=" is buggy. See
1245 L<overload/Copy Constructor>.
1247 =item CORE::%s is not a keyword
1249 (F) The CORE:: namespace is reserved for Perl keywords.
1251 =item corrupted regexp pointers
1253 (P) The regular expression engine got confused by what the regular
1254 expression compiler gave it.
1256 =item corrupted regexp program
1258 (P) The regular expression engine got passed a regexp program without a
1261 =item Corrupt malloc ptr 0x%lx at 0x%lx
1263 (P) The malloc package that comes with Perl had an internal failure.
1265 =item Count after length/code in unpack
1267 (F) You had an unpack template indicating a counted-length string, but
1268 you have also specified an explicit size for the string. See
1271 =item Deep recursion on subroutine "%s"
1273 (W recursion) This subroutine has called itself (directly or indirectly)
1274 100 times more than it has returned. This probably indicates an
1275 infinite recursion, unless you're writing strange benchmark programs, in
1276 which case it indicates something else.
1278 =item defined(@array) is deprecated
1280 (D deprecated) defined() is not usually useful on arrays because it
1281 checks for an undefined I<scalar> value. If you want to see if the
1282 array is empty, just use C<if (@array) { # not empty }> for example.
1284 =item defined(%hash) is deprecated
1286 (D deprecated) defined() is not usually useful on hashes because it
1287 checks for an undefined I<scalar> value. If you want to see if the hash
1288 is empty, just use C<if (%hash) { # not empty }> for example.
1290 =item %s defines neither package nor VERSION--version check failed
1292 (F) You said something like "use Module 42" but in the Module file
1293 there are neither package declarations nor a C<$VERSION>.
1295 =item Delimiter for here document is too long
1297 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1298 long for Perl to handle. You have to be seriously twisted to write code
1299 that triggers this error.
1301 =item DESTROY created new reference to dead object '%s'
1303 (F) A DESTROY() method created a new reference to the object which is
1304 just being DESTROYed. Perl is confused, and prefers to abort rather than
1305 to create a dangling reference.
1307 =item Did not produce a valid header
1311 =item %s did not return a true value
1313 (F) A required (or used) file must return a true value to indicate that
1314 it compiled correctly and ran its initialization code correctly. It's
1315 traditional to end such a file with a "1;", though any true value would
1316 do. See L<perlfunc/require>.
1318 =item (Did you mean &%s instead?)
1320 (W) You probably referred to an imported subroutine &FOO as $FOO or some
1323 =item (Did you mean "local" instead of "our"?)
1325 (W misc) Remember that "our" does not localize the declared global
1326 variable. You have declared it again in the same lexical scope, which
1329 =item (Did you mean $ or @ instead of %?)
1331 (W) You probably said %hash{$key} when you meant $hash{$key} or
1332 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1337 (F) You passed die() an empty string (the equivalent of C<die "">) or
1338 you called it with no args and both C<$@> and C<$_> were empty.
1340 =item Document contains no data
1344 =item %s does not define %s::VERSION--version check failed
1346 (F) You said something like "use Module 42" but the Module did not
1347 define a C<$VERSION.>
1349 =item '/' does not take a repeat count
1351 (F) You cannot put a repeat count of any kind right after the '/' code.
1352 See L<perlfunc/pack>.
1354 =item Don't know how to handle magic of type '%s'
1356 (P) The internal handling of magical variables has been cursed.
1358 =item do_study: out of memory
1360 (P) This should have been caught by safemalloc() instead.
1362 =item (Do you need to predeclare %s?)
1364 (S syntax) This is an educated guess made in conjunction with the message
1365 "%s found where operator expected". It often means a subroutine or module
1366 name is being referenced that hasn't been declared yet. This may be
1367 because of ordering problems in your file, or because of a missing
1368 "sub", "package", "require", or "use" statement. If you're referencing
1369 something that isn't defined yet, you don't actually have to define the
1370 subroutine or package before the current location. You can use an empty
1371 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1373 =item dump() better written as CORE::dump()
1375 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1376 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1378 =item Duplicate free() ignored
1380 (S malloc) An internal routine called free() on something that had
1383 =item Duplicate modifier '%c' after '%c' in %s
1385 (W) You have applied the same modifier more than once after a type
1386 in a pack template. See L<perlfunc/pack>.
1388 =item elseif should be elsif
1390 (S syntax) There is no keyword "elseif" in Perl because Larry thinks it's
1391 ugly. Your code will be interpreted as an attempt to call a method named
1392 "elseif" for the class returned by the following block. This is
1393 unlikely to be what you want.
1397 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1398 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1399 a regular expression without specifying the property name.
1401 =item entering effective %s failed
1403 (F) While under the C<use filetest> pragma, switching the real and
1404 effective uids or gids failed.
1406 =item %ENV is aliased to %s
1408 (F) You're running under taint mode, and the C<%ENV> variable has been
1409 aliased to another hash, so it doesn't reflect anymore the state of the
1410 program's environment. This is potentially insecure.
1412 =item Error converting file specification %s
1414 (F) An error peculiar to VMS. Because Perl may have to deal with file
1415 specifications in either VMS or Unix syntax, it converts them to a
1416 single form when it must operate on them directly. Either you've passed
1417 an invalid file specification to Perl, or you've found a case the
1418 conversion routines don't handle. Drat.
1420 =item %s: Eval-group in insecure regular expression
1422 (F) Perl detected tainted data when trying to compile a regular
1423 expression that contains the C<(?{ ... })> zero-width assertion, which
1424 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1426 =item %s: Eval-group not allowed at run time
1428 (F) Perl tried to compile a regular expression containing the
1429 C<(?{ ... })> zero-width assertion at run time, as it would when the
1430 pattern contains interpolated values. Since that is a security risk, it
1431 is not allowed. If you insist, you may still do this by explicitly
1432 building the pattern from an interpolated string at run time and using
1433 that in an eval(). See L<perlre/(?{ code })>.
1435 =item %s: Eval-group not allowed, use re 'eval'
1437 (F) A regular expression contained the C<(?{ ... })> zero-width
1438 assertion, but that construct is only allowed when the C<use re 'eval'>
1439 pragma is in effect. See L<perlre/(?{ code })>.
1441 =item Excessively long <> operator
1443 (F) The contents of a <> operator may not exceed the maximum size of a
1444 Perl identifier. If you're just trying to glob a long list of
1445 filenames, try using the glob() operator, or put the filenames into a
1446 variable and glob that.
1448 =item exec? I'm not *that* kind of operating system
1450 (F) The C<exec> function is not implemented in MacPerl. See L<perlport>.
1452 =item Execution of %s aborted due to compilation errors
1454 (F) The final summary message when a Perl compilation fails.
1456 =item Exiting eval via %s
1458 (W exiting) You are exiting an eval by unconventional means, such as a
1459 goto, or a loop control statement.
1461 =item Exiting format via %s
1463 (W exiting) You are exiting a format by unconventional means, such as a
1464 goto, or a loop control statement.
1466 =item Exiting pseudo-block via %s
1468 (W exiting) You are exiting a rather special block construct (like a
1469 sort block or subroutine) by unconventional means, such as a goto, or a
1470 loop control statement. See L<perlfunc/sort>.
1472 =item Exiting subroutine via %s
1474 (W exiting) You are exiting a subroutine by unconventional means, such
1475 as a goto, or a loop control statement.
1477 =item Exiting substitution via %s
1479 (W exiting) You are exiting a substitution by unconventional means, such
1480 as a return, a goto, or a loop control statement.
1482 =item Explicit blessing to '' (assuming package main)
1484 (W misc) You are blessing a reference to a zero length string. This has
1485 the effect of blessing the reference into the package main. This is
1486 usually not what you want. Consider providing a default target package,
1487 e.g. bless($ref, $p || 'MyPackage');
1489 =item %s: Expression syntax
1491 (A) You've accidentally run your script through B<csh> instead of Perl.
1492 Check the #! line, or manually feed your script into Perl yourself.
1494 =item %s failed--call queue aborted
1496 (F) An untrapped exception was raised while executing a CHECK, INIT, or
1497 END subroutine. Processing of the remainder of the queue of such
1498 routines has been prematurely ended.
1500 =item False [] range "%s" in regex; marked by <-- HERE in m/%s/
1502 (W regexp) A character class range must start and end at a literal
1503 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1504 in your false range is interpreted as a literal "-". Consider quoting the
1505 "-", "\-". The <-- HERE shows in the regular expression about where the
1506 problem was discovered. See L<perlre>.
1508 =item Fatal VMS error at %s, line %d
1510 (P) An error peculiar to VMS. Something untoward happened in a VMS
1511 system service or RTL routine; Perl's exit status should provide more
1512 details. The filename in "at %s" and the line number in "line %d" tell
1513 you which section of the Perl source code is distressed.
1515 =item fcntl is not implemented
1517 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1518 PDP-11 or something?
1520 =item Filehandle %s opened only for input
1522 (W io) You tried to write on a read-only filehandle. If you intended
1523 it to be a read-write filehandle, you needed to open it with "+<" or
1524 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1525 write the file, use ">" or ">>". See L<perlfunc/open>.
1527 =item Filehandle %s opened only for output
1529 (W io) You tried to read from a filehandle opened only for writing, If
1530 you intended it to be a read/write filehandle, you needed to open it
1531 with "+<" or "+>" or "+>>" instead of with "<" or nothing. If you
1532 intended only to read from the file, use "<". See L<perlfunc/open>.
1533 Another possibility is that you attempted to open filedescriptor 0
1534 (also known as STDIN) for output (maybe you closed STDIN earlier?).
1536 =item Filehandle %s reopened as %s only for input
1538 (W io) You opened for reading a filehandle that got the same filehandle id
1539 as STDOUT or STDERR. This occured because you closed STDOUT or STDERR
1542 =item Filehandle STDIN reopened as %s only for output
1544 (W io) You opened for writing a filehandle that got the same filehandle id
1545 as STDIN. This occured because you closed STDIN previously.
1547 =item Final $ should be \$ or $name
1549 (F) You must now decide whether the final $ in a string was meant to be
1550 a literal dollar sign, or was meant to introduce a variable name that
1551 happens to be missing. So you have to put either the backslash or the
1554 =item flock() on closed filehandle %s
1556 (W closed) The filehandle you're attempting to flock() got itself closed
1557 some time before now. Check your control flow. flock() operates on
1558 filehandles. Are you attempting to call flock() on a dirhandle by the
1561 =item Format not terminated
1563 (F) A format must be terminated by a line with a solitary dot. Perl got
1564 to the end of your file without finding such a line.
1566 =item Format %s redefined
1568 (W redefine) You redefined a format. To suppress this warning, say
1571 no warnings 'redefine';
1572 eval "format NAME =...";
1575 =item Found = in conditional, should be ==
1585 (or something like that).
1587 =item %s found where operator expected
1589 (S syntax) The Perl lexer knows whether to expect a term or an operator.
1590 If it sees what it knows to be a term when it was expecting to see an
1591 operator, it gives you this warning. Usually it indicates that an
1592 operator or delimiter was omitted, such as a semicolon.
1594 =item gdbm store returned %d, errno %d, key "%s"
1596 (S) A warning from the GDBM_File extension that a store failed.
1598 =item gethostent not implemented
1600 (F) Your C library apparently doesn't implement gethostent(), probably
1601 because if it did, it'd feel morally obligated to return every hostname
1604 =item get%sname() on closed socket %s
1606 (W closed) You tried to get a socket or peer socket name on a closed
1607 socket. Did you forget to check the return value of your socket() call?
1609 =item getpwnam returned invalid UIC %#o for user "%s"
1611 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1612 C<getpwnam> operator returned an invalid UIC.
1614 =item getsockopt() on closed socket %s
1616 (W closed) You tried to get a socket option on a closed socket. Did you
1617 forget to check the return value of your socket() call? See
1618 L<perlfunc/getsockopt>.
1620 =item Global symbol "%s" requires explicit package name
1622 (F) You've said "use strict vars", which indicates that all variables
1623 must either be lexically scoped (using "my"), declared beforehand using
1624 "our", or explicitly qualified to say which package the global variable
1627 =item glob failed (%s)
1629 (W glob) Something went wrong with the external program(s) used for
1630 C<glob> and C<< <*.c> >>. Usually, this means that you supplied a
1631 C<glob> pattern that caused the external program to fail and exit with a
1632 nonzero status. If the message indicates that the abnormal exit
1633 resulted in a coredump, this may also mean that your csh (C shell) is
1634 broken. If so, you should change all of the csh-related variables in
1635 config.sh: If you have tcsh, make the variables refer to it as if it
1636 were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them all
1637 empty (except that C<d_csh> should be C<'undef'>) so that Perl will
1638 think csh is missing. In either case, after editing config.sh, run
1639 C<./Configure -S> and rebuild Perl.
1641 =item Glob not terminated
1643 (F) The lexer saw a left angle bracket in a place where it was expecting
1644 a term, so it's looking for the corresponding right angle bracket, and
1645 not finding it. Chances are you left some needed parentheses out
1646 earlier in the line, and you really meant a "less than".
1648 =item Got an error from DosAllocMem
1650 (P) An error peculiar to OS/2. Most probably you're using an obsolete
1651 version of Perl, and this should not happen anyway.
1653 =item goto must have label
1655 (F) Unlike with "next" or "last", you're not allowed to goto an
1656 unspecified destination. See L<perlfunc/goto>.
1658 =item ()-group starts with a count
1660 (F) A ()-group started with a count. A count is
1661 supposed to follow something: a template character or a ()-group.
1662 See L<perlfunc/pack>.
1664 =item %s had compilation errors
1666 (F) The final summary message when a C<perl -c> fails.
1668 =item Had to create %s unexpectedly
1670 (S internal) A routine asked for a symbol from a symbol table that ought
1671 to have existed already, but for some reason it didn't, and had to be
1672 created on an emergency basis to prevent a core dump.
1674 =item Hash %%s missing the % in argument %d of %s()
1676 (D deprecated) Really old Perl let you omit the % on hash names in some
1677 spots. This is now heavily deprecated.
1679 =item %s has too many errors
1681 (F) The parser has given up trying to parse the program after 10 errors.
1682 Further error messages would likely be uninformative.
1684 =item Hexadecimal number > 0xffffffff non-portable
1686 (W portable) The hexadecimal number you specified is larger than 2**32-1
1687 (4294967295) and therefore non-portable between systems. See
1688 L<perlport> for more on portability concerns.
1690 =item Identifier too long
1692 (F) Perl limits identifiers (names for variables, functions, etc.) to
1693 about 250 characters for simple names, and somewhat more for compound
1694 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
1695 of Perl are likely to eliminate these arbitrary limitations.
1697 =item Illegal binary digit %s
1699 (F) You used a digit other than 0 or 1 in a binary number.
1701 =item Illegal binary digit %s ignored
1703 (W digit) You may have tried to use a digit other than 0 or 1 in a
1704 binary number. Interpretation of the binary number stopped before the
1707 =item Illegal character %s (carriage return)
1709 (F) Perl normally treats carriage returns in the program text as it
1710 would any other whitespace, which means you should never see this error
1711 when Perl was built using standard options. For some reason, your
1712 version of Perl appears to have been built without this support. Talk
1713 to your Perl administrator.
1715 =item Illegal character in prototype for %s : %s
1717 (W syntax) An illegal character was found in a prototype declaration. Legal
1718 characters in prototypes are $, @, %, *, ;, [, ], &, and \.
1720 =item Illegal declaration of anonymous subroutine
1722 (F) When using the C<sub> keyword to construct an anonymous subroutine,
1723 you must always specify a block of code. See L<perlsub>.
1725 =item Illegal division by zero
1727 (F) You tried to divide a number by 0. Either something was wrong in
1728 your logic, or you need to put a conditional in to guard against
1731 =item Illegal hexadecimal digit %s ignored
1733 (W digit) You may have tried to use a character other than 0 - 9 or
1734 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
1735 number stopped before the illegal character.
1737 =item Illegal modulus zero
1739 (F) You tried to divide a number by 0 to get the remainder. Most
1740 numbers don't take to this kindly.
1742 =item Illegal number of bits in vec
1744 (F) The number of bits in vec() (the third argument) must be a power of
1745 two from 1 to 32 (or 64, if your platform supports that).
1747 =item Illegal octal digit %s
1749 (F) You used an 8 or 9 in an octal number.
1751 =item Illegal octal digit %s ignored
1753 (W digit) You may have tried to use an 8 or 9 in an octal number.
1754 Interpretation of the octal number stopped before the 8 or 9.
1756 =item Illegal switch in PERL5OPT: %s
1758 (X) The PERL5OPT environment variable may only be used to set the
1759 following switches: B<-[DIMUdmtw]>.
1761 =item Ill-formed CRTL environ value "%s"
1763 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
1764 internal environ array, and encountered an element without the C<=>
1765 delimiter used to separate keys from values. The element is ignored.
1767 =item Ill-formed message in prime_env_iter: |%s|
1769 (W internal) A warning peculiar to VMS. Perl tried to read a logical
1770 name or CLI symbol definition when preparing to iterate over %ENV, and
1771 didn't see the expected delimiter between key and value, so the line was
1774 =item Impossible to activate assertion call
1776 (W assertions) You're calling an assertion function in a block that is
1777 not under the control of the C<assertions> pragma.
1779 =item (in cleanup) %s
1781 (W misc) This prefix usually indicates that a DESTROY() method raised
1782 the indicated exception. Since destructors are usually called by the
1783 system at arbitrary points during execution, and often a vast number of
1784 times, the warning is issued only once for any number of failures that
1785 would otherwise result in the same message being repeated.
1787 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
1788 also result in this warning. See L<perlcall/G_KEEPERR>.
1790 =item In EBCDIC the v-string components cannot exceed 2147483647
1792 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
1793 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
1794 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
1796 =item Insecure dependency in %s
1798 (F) You tried to do something that the tainting mechanism didn't like.
1799 The tainting mechanism is turned on when you're running setuid or
1800 setgid, or when you specify B<-T> to turn it on explicitly. The
1801 tainting mechanism labels all data that's derived directly or indirectly
1802 from the user, who is considered to be unworthy of your trust. If any
1803 such data is used in a "dangerous" operation, you get this error. See
1804 L<perlsec> for more information.
1806 =item Insecure directory in %s
1808 (F) You can't use system(), exec(), or a piped open in a setuid or
1809 setgid script if C<$ENV{PATH}> contains a directory that is writable by
1810 the world. See L<perlsec>.
1812 =item Insecure $ENV{%s} while running %s
1814 (F) You can't use system(), exec(), or a piped open in a setuid or
1815 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
1816 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
1817 supplied (or potentially supplied) by the user. The script must set
1818 the path to a known value, using trustworthy data. See L<perlsec>.
1820 =item Integer overflow in %s number
1822 (W overflow) The hexadecimal, octal or binary number you have specified
1823 either as a literal or as an argument to hex() or oct() is too big for
1824 your architecture, and has been converted to a floating point number.
1825 On a 32-bit architecture the largest hexadecimal, octal or binary number
1826 representable without overflow is 0xFFFFFFFF, 037777777777, or
1827 0b11111111111111111111111111111111 respectively. Note that Perl
1828 transparently promotes all numbers to a floating point representation
1829 internally--subject to loss of precision errors in subsequent
1832 =item Integer overflow in version
1834 (F) Some portion of a version initialization is too large for the
1835 size of integers for your architecture. This is not a warning
1836 because there is no rational reason for a version to try and use a
1837 element larger than typically 2**32. This is usually caused by
1838 trying to use some odd mathematical operation as a version, like
1841 =item Internal disaster in regex; marked by <-- HERE in m/%s/
1843 (P) Something went badly wrong in the regular expression parser.
1844 The <-- HERE shows in the regular expression about where the problem was
1847 =item Internal inconsistency in tracking vforks
1849 (S) A warning peculiar to VMS. Perl keeps track of the number of times
1850 you've called C<fork> and C<exec>, to determine whether the current call
1851 to C<exec> should affect the current script or a subprocess (see
1852 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
1853 Perl is making a guess and treating this C<exec> as a request to
1854 terminate the Perl script and execute the specified command.
1856 =item Internal urp in regex; marked by <-- HERE in m/%s/
1858 (P) Something went badly awry in the regular expression parser. The
1859 <-- HERE shows in the regular expression about where the problem was
1862 =item %s (...) interpreted as function
1864 (W syntax) You've run afoul of the rule that says that any list operator
1865 followed by parentheses turns into a function, with all the list
1866 operators arguments found inside the parentheses. See
1867 L<perlop/Terms and List Operators (Leftward)>.
1869 =item Invalid %s attribute: %s
1871 The indicated attribute for a subroutine or variable was not recognized
1872 by Perl or by a user-supplied handler. See L<attributes>.
1874 =item Invalid %s attributes: %s
1876 The indicated attributes for a subroutine or variable were not
1877 recognized by Perl or by a user-supplied handler. See L<attributes>.
1879 =item Invalid conversion in %s: "%s"
1881 (W printf) Perl does not understand the given format conversion. See
1882 L<perlfunc/sprintf>.
1884 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
1886 (F) The range specified in a character class had a minimum character
1887 greater than the maximum character. One possibility is that you forgot the
1888 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
1889 up to C<ff>. The <-- HERE shows in the regular expression about where the
1890 problem was discovered. See L<perlre>.
1892 =item Invalid range "%s" in transliteration operator
1894 (F) The range specified in the tr/// or y/// operator had a minimum
1895 character greater than the maximum character. See L<perlop>.
1897 =item Invalid separator character %s in attribute list
1899 (F) Something other than a colon or whitespace was seen between the
1900 elements of an attribute list. If the previous attribute had a
1901 parenthesised parameter list, perhaps that list was terminated too soon.
1904 =item Invalid separator character %s in PerlIO layer specification %s
1906 (W layer) When pushing layers onto the Perl I/O system, something other than a
1907 colon or whitespace was seen between the elements of a layer list.
1908 If the previous attribute had a parenthesised parameter list, perhaps that
1909 list was terminated too soon.
1911 =item Invalid type '%s' in %s
1913 (F) The given character is not a valid pack or unpack type.
1914 See L<perlfunc/pack>.
1915 (W) The given character is not a valid pack or unpack type but used to be
1918 =item Invalid version format (multiple underscores)
1920 (F) Versions may contain at most a single underscore, which signals
1921 that the version is a beta release. See L<version> for the allowed
1924 =item Invalid version format (underscores before decimal)
1926 (F) Versions may not contain decimals after the optional underscore.
1927 See L<version> for the allowed version formats.
1929 =item ioctl is not implemented
1931 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1932 strange for a machine that supports C.
1934 =item ioctl() on unopened %s
1936 (W unopened) You tried ioctl() on a filehandle that was never opened.
1937 Check you control flow and number of arguments.
1939 =item IO layers (like "%s") unavailable
1941 (F) Your Perl has not been configured to have PerlIO, and therefore
1942 you cannot use IO layers. To have PerlIO Perl must be configured
1945 =item IO::Socket::atmark not implemented on this architecture
1947 (F) Your machine doesn't implement the sockatmark() functionality,
1948 neither as a system call or an ioctl call (SIOCATMARK).
1950 =item $* is no longer supported
1952 (D deprecated) The special variable C<$*>, deprecated in older perls, has
1953 been removed as of 5.9.0 and is no longer supported. You should use the
1954 C<//m> and C<//s> regexp modifiers instead.
1956 =item `%s' is not a code reference
1958 (W overload) The second (fourth, sixth, ...) argument of overload::constant
1959 needs to be a code reference. Either an anonymous subroutine, or a reference
1962 =item `%s' is not an overloadable type
1964 (W overload) You tried to overload a constant type the overload package is
1967 =item junk on end of regexp
1969 (P) The regular expression parser is confused.
1971 =item Label not found for "last %s"
1973 (F) You named a loop to break out of, but you're not currently in a loop
1974 of that name, not even if you count where you were called from. See
1977 =item Label not found for "next %s"
1979 (F) You named a loop to continue, but you're not currently in a loop of
1980 that name, not even if you count where you were called from. See
1983 =item Label not found for "redo %s"
1985 (F) You named a loop to restart, but you're not currently in a loop of
1986 that name, not even if you count where you were called from. See
1989 =item leaving effective %s failed
1991 (F) While under the C<use filetest> pragma, switching the real and
1992 effective uids or gids failed.
1994 =item length/code after end of string in unpack
1996 (F) While unpacking, the string buffer was alread used up when an unpack
1997 length/code combination tried to obtain more data. This results in
1998 an undefined value for the length. See L<perlfunc/pack>.
2000 =item listen() on closed socket %s
2002 (W closed) You tried to do a listen on a closed socket. Did you forget
2003 to check the return value of your socket() call? See
2006 =item Lookbehind longer than %d not implemented in regex; marked by <-- HERE in m/%s/
2008 (F) There is currently a limit on the length of string which lookbehind can
2009 handle. This restriction may be eased in a future release. The <-- HERE
2010 shows in the regular expression about where the problem was discovered.
2012 =item lstat() on filehandle %s
2014 (W io) You tried to do an lstat on a filehandle. What did you mean
2015 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2016 instead on the filehandle.)
2018 =item Lvalue subs returning %s not implemented yet
2020 (F) Due to limitations in the current implementation, array and hash
2021 values cannot be returned in subroutines used in lvalue context. See
2022 L<perlsub/"Lvalue subroutines">.
2024 =item Malformed integer in [] in pack
2026 (F) Between the brackets enclosing a numeric repeat count only digits
2027 are permitted. See L<perlfunc/pack>.
2029 =item Malformed integer in [] in unpack
2031 (F) Between the brackets enclosing a numeric repeat count only digits
2032 are permitted. See L<perlfunc/pack>.
2034 =item Malformed PERLLIB_PREFIX
2036 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2043 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2044 a builtin library search path, prefix2 is substituted. The error may
2045 appear if components are not found, or are too long. See
2046 "PERLLIB_PREFIX" in L<perlos2>.
2048 =item Malformed prototype for %s: %s
2050 (F) You tried to use a function with a malformed prototype. The
2051 syntax of function prototypes is given a brief compile-time check for
2052 obvious errors like invalid characters. A more rigorous check is run
2053 when the function is called.
2055 =item Malformed UTF-8 character (%s)
2057 Perl detected something that didn't comply with UTF-8 encoding rules.
2059 One possible cause is that you read in data that you thought to be in
2060 UTF-8 but it wasn't (it was for example legacy 8-bit data). Another
2061 possibility is careless use of utf8::upgrade().
2063 =item Malformed UTF-16 surrogate
2065 Perl thought it was reading UTF-16 encoded character data but while
2066 doing it Perl met a malformed Unicode surrogate.
2068 =item %s matches null string many times in regex; marked by <-- HERE in m/%s/
2070 (W regexp) The pattern you've specified would be an infinite loop if the
2071 regular expression engine didn't specifically check for that. The <-- HERE
2072 shows in the regular expression about where the problem was discovered.
2075 =item "%s" may clash with future reserved word
2077 (W) This warning may be due to running a perl5 script through a perl4
2078 interpreter, especially if the word that is being warned about is
2081 =item % may not be used in pack
2083 (F) You can't pack a string by supplying a checksum, because the
2084 checksumming process loses information, and you can't go the other way.
2085 See L<perlfunc/unpack>.
2087 =item Method for operation %s not found in package %s during blessing
2089 (F) An attempt was made to specify an entry in an overloading table that
2090 doesn't resolve to a valid subroutine. See L<overload>.
2092 =item Method %s not permitted
2096 =item Might be a runaway multi-line %s string starting on line %d
2098 (S) An advisory indicating that the previous error may have been caused
2099 by a missing delimiter on a string or pattern, because it eventually
2100 ended earlier on the current line.
2102 =item Misplaced _ in number
2104 (W syntax) An underscore (underbar) in a numeric constant did not
2105 separate two digits.
2107 =item Missing %sbrace%s on \N{}
2109 (F) Wrong syntax of character name literal C<\N{charname}> within
2110 double-quotish context.
2112 =item Missing comma after first argument to %s function
2114 (F) While certain functions allow you to specify a filehandle or an
2115 "indirect object" before the argument list, this ain't one of them.
2117 =item Missing command in piped open
2119 (W pipe) You used the C<open(FH, "| command")> or
2120 C<open(FH, "command |")> construction, but the command was missing or
2123 =item Missing control char name in \c
2125 (F) A double-quoted string ended with "\c", without the required control
2128 =item Missing name in "my sub"
2130 (F) The reserved syntax for lexically scoped subroutines requires that
2131 they have a name with which they can be found.
2133 =item Missing $ on loop variable
2135 (F) Apparently you've been programming in B<csh> too much. Variables
2136 are always mentioned with the $ in Perl, unlike in the shells, where it
2137 can vary from one line to the next.
2139 =item (Missing operator before %s?)
2141 (S syntax) This is an educated guess made in conjunction with the message
2142 "%s found where operator expected". Often the missing operator is a comma.
2144 =item Missing right brace on %s
2146 (F) Missing right brace in C<\p{...}> or C<\P{...}>.
2148 =item Missing right curly or square bracket
2150 (F) The lexer counted more opening curly or square brackets than closing
2151 ones. As a general rule, you'll find it's missing near the place you
2154 =item (Missing semicolon on previous line?)
2156 (S syntax) This is an educated guess made in conjunction with the message
2157 "%s found where operator expected". Don't automatically put a semicolon on
2158 the previous line just because you saw this message.
2160 =item Modification of a read-only value attempted
2162 (F) You tried, directly or indirectly, to change the value of a
2163 constant. You didn't, of course, try "2 = 1", because the compiler
2164 catches that. But an easy way to do the same thing is:
2166 sub mod { $_[0] = 1 }
2169 Another way is to assign to a substr() that's off the end of the string.
2171 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2172 is aliased to a constant in the look I<LIST>:
2175 foreach my $n ($x, 2) {
2176 $n *= 2; # modifies the $x, but fails on attempt to modify the 2
2179 =item Modification of non-creatable array value attempted, %s
2181 (F) You tried to make an array value spring into existence, and the
2182 subscript was probably negative, even counting from end of the array
2185 =item Modification of non-creatable hash value attempted, %s
2187 (P) You tried to make a hash value spring into existence, and it
2188 couldn't be created for some peculiar reason.
2190 =item Module name must be constant
2192 (F) Only a bare module name is allowed as the first argument to a "use".
2194 =item Module name required with -%c option
2196 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2197 you omitted the name of the module. Consult L<perlrun> for full details
2198 about C<-M> and C<-m>.
2200 =item More than one argument to open
2202 (F) The C<open> function has been asked to open multiple files. This
2203 can happen if you are trying to open a pipe to a command that takes a
2204 list of arguments, but have forgotten to specify a piped open mode.
2205 See L<perlfunc/open> for details.
2207 =item msg%s not implemented
2209 (F) You don't have System V message IPC on your system.
2211 =item Multidimensional syntax %s not supported
2213 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2214 They're written like C<$foo[1][2][3]>, as in C.
2216 =item '/' must be followed by 'a*', 'A*' or 'Z*'
2218 (F) You had a pack template indicating a counted-length string,
2219 Currently the only things that can have their length counted are a*, A*
2220 or Z*. See L<perlfunc/pack>.
2222 =item '/' must follow a numeric type in unpack
2224 (F) You had an unpack template that contained a '/', but this did not
2225 follow some unpack specification producing a numeric value.
2226 See L<perlfunc/pack>.
2228 =item "my sub" not yet implemented
2230 (F) Lexically scoped subroutines are not yet implemented. Don't try
2233 =item "my" variable %s can't be in a package
2235 (F) Lexically scoped variables aren't in a package, so it doesn't make
2236 sense to try to declare one with a package qualifier on the front. Use
2237 local() if you want to localize a package variable.
2239 =item Name "%s::%s" used only once: possible typo
2241 (W once) Typographical errors often show up as unique variable names.
2242 If you had a good reason for having a unique name, then just mention it
2243 again somehow to suppress the message. The C<our> declaration is
2244 provided for this purpose.
2246 NOTE: This warning detects symbols that have been used only once so $c, @c,
2247 %c, *c, &c, sub c{}, c(), and c (the filehandle or format) are considered
2248 the same; if a program uses $c only once but also uses any of the others it
2249 will not trigger this warning.
2251 =item Negative '/' count in unpack
2253 (F) The length count obtained from a length/code unpack operation was
2254 negative. See L<perlfunc/pack>.
2256 =item Negative length
2258 (F) You tried to do a read/write/send/recv operation with a buffer
2259 length that is less than 0. This is difficult to imagine.
2261 =item Negative offset to vec in lvalue context
2263 (F) When C<vec> is called in an lvalue context, the second argument must be
2264 greater than or equal to zero.
2266 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
2268 (F) You can't quantify a quantifier without intervening parentheses. So
2269 things like ** or +* or ?* are illegal. The <-- HERE shows in the regular
2270 expression about where the problem was discovered.
2272 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
2273 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
2275 =item %s never introduced
2277 (S internal) The symbol in question was declared but somehow went out of
2278 scope before it could possibly have been used.
2280 =item Newline in left-justified string for %s
2282 (W printf) There is a newline in a string to be left justified by
2283 C<printf> or C<sprintf>.
2285 The padding spaces will appear after the newline, which is probably not
2286 what you wanted. Usually you should remove the newline from the string
2287 and put formatting characters in the C<sprintf> format.
2289 =item No %s allowed while running setuid
2291 (F) Certain operations are deemed to be too insecure for a setuid or
2292 setgid script to even be allowed to attempt. Generally speaking there
2293 will be another way to do what you want that is, if not secure, at least
2294 securable. See L<perlsec>.
2296 =item No comma allowed after %s
2298 (F) A list operator that has a filehandle or "indirect object" is not
2299 allowed to have a comma between that and the following arguments.
2300 Otherwise it'd be just another one of the arguments.
2302 One possible cause for this is that you expected to have imported a
2303 constant to your name space with B<use> or B<import> while no such
2304 importing took place, it may for example be that your operating system
2305 does not support that particular constant. Hopefully you did use an
2306 explicit import list for the constants you expect to see, please see
2307 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
2308 would probably have caught this error earlier it naturally does not
2309 remedy the fact that your operating system still does not support that
2310 constant. Maybe you have a typo in the constants of the symbol import
2311 list of B<use> or B<import> or in the constant name at the line where
2312 this error was triggered?
2314 =item No command into which to pipe on command line
2316 (F) An error peculiar to VMS. Perl handles its own command line
2317 redirection, and found a '|' at the end of the command line, so it
2318 doesn't know where you want to pipe the output from this command.
2320 =item No DB::DB routine defined
2322 (F) The currently executing code was compiled with the B<-d> switch, but
2323 for some reason the perl5db.pl file (or some facsimile thereof) didn't
2324 define a routine to be called at the beginning of each statement. Which
2325 is odd, because the file should have been required automatically, and
2326 should have blown up the require if it didn't parse right.
2328 =item No dbm on this machine
2330 (P) This is counted as an internal error, because every machine should
2331 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
2333 =item No DBsub routine
2335 (F) The currently executing code was compiled with the B<-d> switch,
2336 but for some reason the perl5db.pl file (or some facsimile thereof)
2337 didn't define a DB::sub routine to be called at the beginning of each
2338 ordinary subroutine call.
2340 =item No B<-e> allowed in setuid scripts
2342 (F) A setuid script can't be specified by the user.
2344 =item No error file after 2> or 2>> on command line
2346 (F) An error peculiar to VMS. Perl handles its own command line
2347 redirection, and found a '2>' or a '2>>' on the command line, but can't
2348 find the name of the file to which to write data destined for stderr.
2350 =item No group ending character '%c' found in template
2352 (F) A pack or unpack template has an opening '(' or '[' without its
2353 matching counterpart. See L<perlfunc/pack>.
2355 =item No input file after < on command line
2357 (F) An error peculiar to VMS. Perl handles its own command line
2358 redirection, and found a '<' on the command line, but can't find the
2359 name of the file from which to read data for stdin.
2363 (F) The setuid emulator requires that scripts have a well-formed #! line
2364 even on machines that don't support the #! construct.
2366 =item "no" not allowed in expression
2368 (F) The "no" keyword is recognized and executed at compile time, and
2369 returns no useful value. See L<perlmod>.
2371 =item No output file after > on command line
2373 (F) An error peculiar to VMS. Perl handles its own command line
2374 redirection, and found a lone '>' at the end of the command line, so it
2375 doesn't know where you wanted to redirect stdout.
2377 =item No output file after > or >> on command line
2379 (F) An error peculiar to VMS. Perl handles its own command line
2380 redirection, and found a '>' or a '>>' on the command line, but can't
2381 find the name of the file to which to write data destined for stdout.
2383 =item No package name allowed for variable %s in "our"
2385 (F) Fully qualified variable names are not allowed in "our"
2386 declarations, because that doesn't make much sense under existing
2387 semantics. Such syntax is reserved for future extensions.
2389 =item No Perl script found in input
2391 (F) You called C<perl -x>, but no line was found in the file beginning
2392 with #! and containing the word "perl".
2394 =item No setregid available
2396 (F) Configure didn't find anything resembling the setregid() call for
2399 =item No setreuid available
2401 (F) Configure didn't find anything resembling the setreuid() call for
2404 =item No space allowed after -%c
2406 (F) The argument to the indicated command line switch must follow
2407 immediately after the switch, without intervening spaces.
2409 =item No %s specified for -%c
2411 (F) The indicated command line switch needs a mandatory argument, but
2412 you haven't specified one.
2414 =item No such class %s
2416 (F) You provided a class qualifier in a "my" or "our" declaration, but
2417 this class doesn't exist at this point in your program.
2419 =item No such pipe open
2421 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
2422 close a pipe which hadn't been opened. This should have been caught
2423 earlier as an attempt to close an unopened filehandle.
2425 =item No such signal: SIG%s
2427 (W signal) You specified a signal name as a subscript to %SIG that was
2428 not recognized. Say C<kill -l> in your shell to see the valid signal
2429 names on your system.
2431 =item Not a CODE reference
2433 (F) Perl was trying to evaluate a reference to a code value (that is, a
2434 subroutine), but found a reference to something else instead. You can
2435 use the ref() function to find out what kind of ref it really was. See
2438 =item Not a format reference
2440 (F) I'm not sure how you managed to generate a reference to an anonymous
2441 format, but this indicates you did, and that it didn't exist.
2443 =item Not a GLOB reference
2445 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
2446 symbol table entry that looks like C<*foo>), but found a reference to
2447 something else instead. You can use the ref() function to find out what
2448 kind of ref it really was. See L<perlref>.
2450 =item Not a HASH reference
2452 (F) Perl was trying to evaluate a reference to a hash value, but found a
2453 reference to something else instead. You can use the ref() function to
2454 find out what kind of ref it really was. See L<perlref>.
2456 =item Not an ARRAY reference
2458 (F) Perl was trying to evaluate a reference to an array value, but found
2459 a reference to something else instead. You can use the ref() function
2460 to find out what kind of ref it really was. See L<perlref>.
2462 =item Not a perl script
2464 (F) The setuid emulator requires that scripts have a well-formed #! line
2465 even on machines that don't support the #! construct. The line must
2468 =item Not a SCALAR reference
2470 (F) Perl was trying to evaluate a reference to a scalar value, but found
2471 a reference to something else instead. You can use the ref() function
2472 to find out what kind of ref it really was. See L<perlref>.
2474 =item Not a subroutine reference
2476 (F) Perl was trying to evaluate a reference to a code value (that is, a
2477 subroutine), but found a reference to something else instead. You can
2478 use the ref() function to find out what kind of ref it really was. See
2481 =item Not a subroutine reference in overload table
2483 (F) An attempt was made to specify an entry in an overloading table that
2484 doesn't somehow point to a valid subroutine. See L<overload>.
2486 =item Not enough arguments for %s
2488 (F) The function requires more arguments than you specified.
2490 =item Not enough format arguments
2492 (W syntax) A format specified more picture fields than the next line
2493 supplied. See L<perlform>.
2497 (A) You've accidentally run your script through the Bourne shell instead
2498 of Perl. Check the #! line, or manually feed your script into Perl
2501 =item no UTC offset information; assuming local time is UTC
2503 (S) A warning peculiar to VMS. Perl was unable to find the local
2504 timezone offset, so it's assuming that local system time is equivalent
2505 to UTC. If it's not, define the logical name
2506 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
2507 need to be added to UTC to get local time.
2509 =item Null filename used
2511 (F) You can't require the null filename, especially because on many
2512 machines that means the current directory! See L<perlfunc/require>.
2514 =item NULL OP IN RUN
2516 (P debugging) Some internal routine called run() with a null opcode
2519 =item Null picture in formline
2521 (F) The first argument to formline must be a valid format picture
2522 specification. It was found to be empty, which probably means you
2523 supplied it an uninitialized value. See L<perlform>.
2527 (P) An attempt was made to realloc NULL.
2529 =item NULL regexp argument
2531 (P) The internal pattern matching routines blew it big time.
2533 =item NULL regexp parameter
2535 (P) The internal pattern matching routines are out of their gourd.
2537 =item Number too long
2539 (F) Perl limits the representation of decimal numbers in programs to
2540 about 250 characters. You've exceeded that length. Future
2541 versions of Perl are likely to eliminate this arbitrary limitation. In
2542 the meantime, try using scientific notation (e.g. "1e6" instead of
2545 =item Octal number in vector unsupported
2547 (F) Numbers with a leading C<0> are not currently allowed in vectors.
2548 The octal number interpretation of such numbers may be supported in a
2551 =item Octal number > 037777777777 non-portable
2553 (W portable) The octal number you specified is larger than 2**32-1
2554 (4294967295) and therefore non-portable between systems. See
2555 L<perlport> for more on portability concerns.
2557 See also L<perlport> for writing portable code.
2559 =item Odd number of arguments for overload::constant
2561 (W overload) The call to overload::constant contained an odd number of
2562 arguments. The arguments should come in pairs.
2564 =item Odd number of elements in anonymous hash
2566 (W misc) You specified an odd number of elements to initialize a hash,
2567 which is odd, because hashes come in key/value pairs.
2569 =item Odd number of elements in hash assignment
2571 (W misc) You specified an odd number of elements to initialize a hash,
2572 which is odd, because hashes come in key/value pairs.
2574 =item Offset outside string
2576 (F) You tried to do a read/write/send/recv operation with an offset
2577 pointing outside the buffer. This is difficult to imagine. The sole
2578 exception to this is that C<sysread()>ing past the buffer will extend
2579 the buffer and zero pad the new area.
2581 =item %s() on unopened %s
2583 (W unopened) An I/O operation was attempted on a filehandle that was
2584 never initialized. You need to do an open(), a sysopen(), or a socket()
2585 call, or call a constructor from the FileHandle package.
2587 =item -%s on unopened filehandle %s
2589 (W unopened) You tried to invoke a file test operator on a filehandle
2590 that isn't open. Check your control flow. See also L<perlfunc/-X>.
2594 (S internal) An internal warning that the grammar is screwed up.
2598 (S internal) An internal warning that the grammar is screwed up.
2600 =item Operation `%s': no method found, %s
2602 (F) An attempt was made to perform an overloaded operation for which no
2603 handler was defined. While some handlers can be autogenerated in terms
2604 of other handlers, there is no default handler for any operation, unless
2605 C<fallback> overloading key is specified to be true. See L<overload>.
2607 =item Operator or semicolon missing before %s
2609 (S ambiguous) You used a variable or subroutine call where the parser
2610 was expecting an operator. The parser has assumed you really meant to
2611 use an operator, but this is highly likely to be incorrect. For
2612 example, if you say "*foo *foo" it will be interpreted as if you said
2615 =item "our" variable %s redeclared
2617 (W misc) You seem to have already declared the same global once before
2618 in the current lexical scope.
2620 =item Out of memory!
2622 (X) The malloc() function returned 0, indicating there was insufficient
2623 remaining memory (or virtual memory) to satisfy the request. Perl has
2624 no option but to exit immediately.
2626 At least in Unix you may be able to get past this by increasing your
2627 process datasize limits: in csh/tcsh use C<limit> and
2628 C<limit datasize n> (where C<n> is the number of kilobytes) to check
2629 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
2630 and C<ulimit -d n>, respectively.
2632 =item Out of memory during "large" request for %s
2634 (F) The malloc() function returned 0, indicating there was insufficient
2635 remaining memory (or virtual memory) to satisfy the request. However,
2636 the request was judged large enough (compile-time default is 64K), so a
2637 possibility to shut down by trapping this error is granted.
2639 =item Out of memory during request for %s
2641 (X|F) The malloc() function returned 0, indicating there was
2642 insufficient remaining memory (or virtual memory) to satisfy the
2645 The request was judged to be small, so the possibility to trap it
2646 depends on the way perl was compiled. By default it is not trappable.
2647 However, if compiled for this, Perl may use the contents of C<$^M> as an
2648 emergency pool after die()ing with this message. In this case the error
2649 is trappable I<once>, and the error message will include the line and file
2650 where the failed request happened.
2652 =item Out of memory during ridiculously large request
2654 (F) You can't allocate more than 2^31+"small amount" bytes. This error
2655 is most likely to be caused by a typo in the Perl program. e.g.,
2656 C<$arr[time]> instead of C<$arr[$time]>.
2658 =item Out of memory for yacc stack
2660 (F) The yacc parser wanted to grow its stack so it could continue
2661 parsing, but realloc() wouldn't give it more memory, virtual or
2664 =item '@' outside of string in unpack
2666 (F) You had a template that specified an absolute position outside
2667 the string being unpacked. See L<perlfunc/pack>.
2669 =item %s package attribute may clash with future reserved word: %s
2671 (W reserved) A lowercase attribute name was used that had a
2672 package-specific handler. That name might have a meaning to Perl itself
2673 some day, even though it doesn't yet. Perhaps you should use a
2674 mixed-case attribute name, instead. See L<attributes>.
2676 =item pack/unpack repeat count overflow
2678 (F) You can't specify a repeat count so large that it overflows your
2679 signed integers. See L<perlfunc/pack>.
2683 (W io) A single call to write() produced more lines than can fit on a
2684 page. See L<perlform>.
2688 (P) An internal error.
2690 =item panic: array extend
2692 (P) An attempt was made to extend an array beyond the largest possible
2695 =item panic: ck_grep
2697 (P) Failed an internal consistency check trying to compile a grep.
2699 =item panic: ck_split
2701 (P) Failed an internal consistency check trying to compile a split.
2703 =item panic: corrupt saved stack index
2705 (P) The savestack was requested to restore more localized values than
2706 there are in the savestack.
2708 =item panic: del_backref
2710 (P) Failed an internal consistency check while trying to reset a weak
2713 =item panic: Devel::DProf inconsistent subroutine return
2715 (P) Devel::DProf called a subroutine that exited using goto(LABEL),
2716 last(LABEL) or next(LABEL). Leaving that way a subroutine called from
2717 an XSUB will lead very probably to a crash of the interpreter. This is
2718 a bug that will hopefully one day get fixed.
2722 (P) We popped the context stack to an eval context, and then discovered
2723 it wasn't an eval context.
2725 =item panic: do_subst
2727 (P) The internal pp_subst() routine was called with invalid operational
2730 =item panic: do_trans_%s
2732 (P) The internal do_trans routines were called with invalid operational
2737 (P) The library function frexp() failed, making printf("%f") impossible.
2741 (P) We popped the context stack to a context with the specified label,
2742 and then discovered it wasn't a context we know how to do a goto in.
2744 =item panic: INTERPCASEMOD
2746 (P) The lexer got into a bad state at a case modifier.
2748 =item panic: INTERPCONCAT
2750 (P) The lexer got into a bad state parsing a string with brackets.
2752 =item panic: kid popen errno read
2754 (F) forked child returned an incomprehensible message about its errno.
2758 (P) We popped the context stack to a block context, and then discovered
2759 it wasn't a block context.
2761 =item panic: leave_scope clearsv
2763 (P) A writable lexical variable became read-only somehow within the
2766 =item panic: leave_scope inconsistency
2768 (P) The savestack probably got out of sync. At least, there was an
2769 invalid enum on the top of it.
2771 =item panic: list extend
2773 (P) An attempt was made to extend a list beyond the largest possible
2776 =item panic: magic_killbackrefs
2778 (P) Failed an internal consistency check while trying to reset all weak
2779 references to an object.
2783 (P) Something requested a negative number of bytes of malloc.
2785 =item panic: mapstart
2787 (P) The compiler is screwed up with respect to the map() function.
2789 =item panic: memory wrap
2791 (P) Something tried to allocate more memory than possible.
2793 =item panic: null array
2795 (P) One of the internal array routines was passed a null AV pointer.
2797 =item panic: pad_alloc
2799 (P) The compiler got confused about which scratch pad it was allocating
2800 and freeing temporaries and lexicals from.
2802 =item panic: pad_free curpad
2804 (P) The compiler got confused about which scratch pad it was allocating
2805 and freeing temporaries and lexicals from.
2807 =item panic: pad_free po
2809 (P) An invalid scratch pad offset was detected internally.
2811 =item panic: pad_reset curpad
2813 (P) The compiler got confused about which scratch pad it was allocating
2814 and freeing temporaries and lexicals from.
2816 =item panic: pad_sv po
2818 (P) An invalid scratch pad offset was detected internally.
2820 =item panic: pad_swipe curpad
2822 (P) The compiler got confused about which scratch pad it was allocating
2823 and freeing temporaries and lexicals from.
2825 =item panic: pad_swipe po
2827 (P) An invalid scratch pad offset was detected internally.
2829 =item panic: pp_iter
2831 (P) The foreach iterator got called in a non-loop context frame.
2833 =item panic: pp_match%s
2835 (P) The internal pp_match() routine was called with invalid operational
2838 =item panic: pp_split
2840 (P) Something terrible went wrong in setting up for the split.
2842 =item panic: realloc
2844 (P) Something requested a negative number of bytes of realloc.
2846 =item panic: restartop
2848 (P) Some internal routine requested a goto (or something like it), and
2849 didn't supply the destination.
2853 (P) We popped the context stack to a subroutine or eval context, and
2854 then discovered it wasn't a subroutine or eval context.
2856 =item panic: scan_num
2858 (P) scan_num() got called on something that wasn't a number.
2860 =item panic: string extend
2862 (P) An attempt was made to extend a string beyond the largest possible
2865 =item panic: sv_insert
2867 (P) The sv_insert() routine was told to remove more string than there
2870 =item panic: top_env
2872 (P) The compiler attempted to do a goto, or something weird like that.
2874 =item panic: utf16_to_utf8: odd bytelen
2876 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
2877 to even) byte length.
2881 (P) The lexer got into a bad state while processing a case modifier.
2883 =item Parentheses missing around "%s" list
2885 (W parenthesis) You said something like
2891 my ($foo, $bar) = @_;
2893 Remember that "my", "our", and "local" bind tighter than comma.
2895 =item C<-p> destination: %s
2897 (F) An error occurred during the implicit output invoked by the C<-p>
2898 command-line switch. (This output goes to STDOUT unless you've
2899 redirected it with select().)
2901 =item (perhaps you forgot to load "%s"?)
2903 (F) This is an educated guess made in conjunction with the message
2904 "Can't locate object method \"%s\" via package \"%s\"". It often means
2905 that a method requires a package that has not been loaded.
2907 =item Perl %s required--this is only version %s, stopped
2909 (F) The module in question uses features of a version of Perl more
2910 recent than the currently running version. How long has it been since
2911 you upgraded, anyway? See L<perlfunc/require>.
2913 =item Perl_my_%s() not available
2915 (F) Your platform has very uncommon byte-order and integer size,
2916 so it was not possible to set up some or all fixed-width byte-order
2917 conversion functions. This is only a problem when you're using the
2918 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
2920 =item PERL_SH_DIR too long
2922 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2923 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
2925 =item PERL_SIGNALS illegal: "%s"
2927 See L<perlrun/PERL_SIGNALS> for legal values.
2929 =item perl: warning: Setting locale failed.
2931 (S) The whole warning message will look something like:
2933 perl: warning: Setting locale failed.
2934 perl: warning: Please check that your locale settings:
2937 are supported and installed on your system.
2938 perl: warning: Falling back to the standard locale ("C").
2940 Exactly what were the failed locale settings varies. In the above the
2941 settings were that the LC_ALL was "En_US" and the LANG had no value.
2942 This error means that Perl detected that you and/or your operating
2943 system supplier and/or system administrator have set up the so-called
2944 locale system but Perl could not use those settings. This was not
2945 dead serious, fortunately: there is a "default locale" called "C" that
2946 Perl can and will use, the script will be run. Before you really fix
2947 the problem, however, you will get the same error message each time
2948 you run Perl. How to really fix the problem can be found in
2949 L<perllocale> section B<LOCALE PROBLEMS>.
2951 =item Permission denied
2953 (F) The setuid emulator in suidperl decided you were up to no good.
2955 =item pid %x not a child
2957 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
2958 process which isn't a subprocess of the current process. While this is
2959 fine from VMS' perspective, it's probably not what you intended.
2961 =item 'P' must have an explicit size in unpack
2963 (F) The unpack format P must have an explicit size, not "*".
2965 =item B<-P> not allowed for setuid/setgid script
2967 (F) The script would have to be opened by the C preprocessor by name,
2968 which provides a race condition that breaks security.
2970 =item POSIX class [:%s:] unknown in regex; marked by <-- HERE in m/%s/
2972 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
2973 shows in the regular expression about where the problem was discovered.
2974 Note that the POSIX character classes do B<not> have the C<is> prefix
2975 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
2976 not C<isprint>. See L<perlre>.
2978 =item POSIX getpgrp can't take an argument
2980 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
2981 the BSD version, which takes a pid.
2983 =item POSIX syntax [%s] belongs inside character classes in regex; marked by <-- HERE in m/%s/
2985 (W regexp) The character class constructs [: :], [= =], and [. .] go
2986 I<inside> character classes, the [] are part of the construct, for example:
2987 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
2988 implemented; they are simply placeholders for future extensions and will
2989 cause fatal errors. The <-- HERE shows in the regular expression about
2990 where the problem was discovered. See L<perlre>.
2992 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
2994 (F regexp) Within regular expression character classes ([]) the syntax
2995 beginning with "[." and ending with ".]" is reserved for future extensions.
2996 If you need to represent those character sequences inside a regular
2997 expression character class, just quote the square brackets with the
2998 backslash: "\[." and ".\]". The <-- HERE shows in the regular expression
2999 about where the problem was discovered. See L<perlre>.
3001 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
3003 (F) Within regular expression character classes ([]) the syntax beginning
3004 with "[=" and ending with "=]" is reserved for future extensions. If you
3005 need to represent those character sequences inside a regular expression
3006 character class, just quote the square brackets with the backslash: "\[="
3007 and "=\]". The <-- HERE shows in the regular expression about where the
3008 problem was discovered. See L<perlre>.
3010 =item Possible attempt to put comments in qw() list
3012 (W qw) qw() lists contain items separated by whitespace; as with literal
3013 strings, comment characters are not ignored, but are instead treated as
3014 literal data. (You may have used different delimiters than the
3015 parentheses shown here; braces are also frequently used.)
3017 You probably wrote something like this:
3024 when you should have written this:
3031 If you really want comments, build your list the
3032 old-fashioned way, with quotes and commas:
3036 'b', # another comment
3039 =item Possible attempt to separate words with commas
3041 (W qw) qw() lists contain items separated by whitespace; therefore
3042 commas aren't needed to separate the items. (You may have used
3043 different delimiters than the parentheses shown here; braces are also
3046 You probably wrote something like this:
3050 which puts literal commas into some of the list items. Write it without
3051 commas if you don't want them to appear in your data:
3055 =item Possible memory corruption: %s overflowed 3rd argument
3057 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
3058 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
3059 end of the buffer just in case. This sentinel byte got clobbered, and
3060 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
3062 =item Possible precedence problem on bitwise %c operator
3064 (W precedence) Your program uses a bitwise logical operator in conjunction
3065 with a numeric comparison operator, like this :
3067 if ($x & $y == 0) { ... }
3069 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
3070 higher precedence of C<==>. This is probably not what you want. (If you
3071 really meant to write this, disable the warning, or, better, put the
3072 parentheses explicitly and write C<$x & ($y == 0)>).
3074 =item Possible unintended interpolation of %s in string
3076 (W ambiguous) You said something like `@foo' in a double-quoted string
3077 but there was no array C<@foo> in scope at the time. If you wanted a
3078 literal @foo, then write it as \@foo; otherwise find out what happened
3079 to the array you apparently lost track of.
3081 =item Possible Y2K bug: %s
3083 (W y2k) You are concatenating the number 19 with another number, which
3084 could be a potential Year 2000 problem.
3086 =item pragma "attrs" is deprecated, use "sub NAME : ATTRS" instead
3088 (D deprecated) You have written something like this:
3092 use attrs qw(locked);
3095 You should use the new declaration syntax instead.
3101 The C<use attrs> pragma is now obsolete, and is only provided for
3102 backward-compatibility. See L<perlsub/"Subroutine Attributes">.
3104 =item Precedence problem: open %s should be open(%s)
3106 (S precedence) The old irregular construct
3110 is now misinterpreted as
3114 because of the strict regularization of Perl 5's grammar into unary and
3115 list operators. (The old open was a little of both.) You must put
3116 parentheses around the filehandle, or use the new "or" operator instead
3119 =item Premature end of script headers
3123 =item printf() on closed filehandle %s
3125 (W closed) The filehandle you're writing to got itself closed sometime
3126 before now. Check your control flow.
3128 =item print() on closed filehandle %s
3130 (W closed) The filehandle you're printing on got itself closed sometime
3131 before now. Check your control flow.
3133 =item Process terminated by SIG%s
3135 (W) This is a standard message issued by OS/2 applications, while *nix
3136 applications die in silence. It is considered a feature of the OS/2
3137 port. One can easily disable this by appropriate sighandlers, see
3138 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
3141 =item Prototype mismatch: %s vs %s
3143 (S prototype) The subroutine being declared or defined had previously been
3144 declared or defined with a different function prototype.
3146 =item Prototype not terminated
3148 (F) You've omitted the closing parenthesis in a function prototype
3151 =item Quantifier follows nothing in regex; marked by <-- HERE in m/%s/
3153 (F) You started a regular expression with a quantifier. Backslash it if you
3154 meant it literally. The <-- HERE shows in the regular expression about
3155 where the problem was discovered. See L<perlre>.
3157 =item Quantifier in {,} bigger than %d in regex; marked by <-- HERE in m/%s/
3159 (F) There is currently a limit to the size of the min and max values of the
3160 {min,max} construct. The <-- HERE shows in the regular expression about where
3161 the problem was discovered. See L<perlre>.
3163 =item Quantifier unexpected on zero-length expression; marked by <-- HERE in m/%s/
3165 (W regexp) You applied a regular expression quantifier in a place where
3166 it makes no sense, such as on a zero-width assertion. Try putting the
3167 quantifier inside the assertion instead. For example, the way to match
3168 "abc" provided that it is followed by three repetitions of "xyz" is
3169 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
3171 The <-- HERE shows in the regular expression about where the problem was
3174 =item Range iterator outside integer range
3176 (F) One (or both) of the numeric arguments to the range operator ".."
3177 are outside the range which can be represented by integers internally.
3178 One possible workaround is to force Perl to use magical string increment
3179 by prepending "0" to your numbers.
3181 =item readline() on closed filehandle %s
3183 (W closed) The filehandle you're reading from got itself closed sometime
3184 before now. Check your control flow.
3186 =item read() on closed filehandle %s
3188 (W closed) You tried to read from a closed filehandle.
3190 =item read() on unopened filehandle %s
3192 (W unopened) You tried to read from a filehandle that was never opened.
3194 =item Reallocation too large: %lx
3196 (F) You can't allocate more than 64K on an MS-DOS machine.
3198 =item realloc() of freed memory ignored
3200 (S malloc) An internal routine called realloc() on something that had
3203 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
3205 (F debugging) You can't use the B<-D> option unless the code to produce
3206 the desired output is compiled into Perl, which entails some overhead,
3207 which is why it's currently left out of your copy.
3209 =item Recursive inheritance detected in package '%s'
3211 (F) More than 100 levels of inheritance were used. Probably indicates
3212 an unintended loop in your inheritance hierarchy.
3214 =item Recursive inheritance detected while looking for method %s
3216 (F) More than 100 levels of inheritance were encountered while invoking
3217 a method. Probably indicates an unintended loop in your inheritance
3220 =item Reference found where even-sized list expected
3222 (W misc) You gave a single reference where Perl was expecting a list
3223 with an even number of elements (for assignment to a hash). This usually
3224 means that you used the anon hash constructor when you meant to use
3225 parens. In any case, a hash requires key/value B<pairs>.
3227 %hash = { one => 1, two => 2, }; # WRONG
3228 %hash = [ qw/ an anon array / ]; # WRONG
3229 %hash = ( one => 1, two => 2, ); # right
3230 %hash = qw( one 1 two 2 ); # also fine
3232 =item Reference is already weak
3234 (W misc) You have attempted to weaken a reference that is already weak.
3235 Doing so has no effect.
3237 =item Reference miscount in sv_replace()
3239 (W internal) The internal sv_replace() function was handed a new SV with
3240 a reference count of other than 1.
3242 =item Reference to nonexistent group in regex; marked by <-- HERE in m/%s/
3244 (F) You used something like C<\7> in your regular expression, but there are
3245 not at least seven sets of capturing parentheses in the expression. If you
3246 wanted to have the character with value 7 inserted into the regular expression,
3247 prepend a zero to make the number at least two digits: C<\07>
3249 The <-- HERE shows in the regular expression about where the problem was
3252 =item regexp memory corruption
3254 (P) The regular expression engine got confused by what the regular
3255 expression compiler gave it.
3257 =item Regexp out of space
3259 (P) A "can't happen" error, because safemalloc() should have caught it
3262 =item Repeated format line will never terminate (~~ and @# incompatible)
3264 (F) Your format containes the ~~ repeat-until-blank sequence and a
3265 numeric field that will never go blank so that the repetition never
3266 terminates. You might use ^# instead. See L<perlform>.
3268 =item Reversed %s= operator
3270 (W syntax) You wrote your assignment operator backwards. The = must
3271 always comes last, to avoid ambiguity with subsequent unary operators.
3273 =item Runaway format
3275 (F) Your format contained the ~~ repeat-until-blank sequence, but it
3276 produced 200 lines at once, and the 200th line looked exactly like the
3277 199th line. Apparently you didn't arrange for the arguments to exhaust
3278 themselves, either by using ^ instead of @ (for scalar variables), or by
3279 shifting or popping (for array variables). See L<perlform>.
3281 =item Scalars leaked: %d
3283 (P) Something went wrong in Perl's internal bookkeeping of scalars:
3284 not all scalar variables were deallocated by the time Perl exited.
3285 What this usually indicates is a memory leak, which is of course bad,
3286 especially if the Perl program is intended to be long-running.
3288 =item Scalar value @%s[%s] better written as $%s[%s]
3290 (W syntax) You've used an array slice (indicated by @) to select a
3291 single element of an array. Generally it's better to ask for a scalar
3292 value (indicated by $). The difference is that C<$foo[&bar]> always
3293 behaves like a scalar, both when assigning to it and when evaluating its
3294 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
3295 and provides a list context to its subscript, which can do weird things
3296 if you're expecting only one subscript.
3298 On the other hand, if you were actually hoping to treat the array
3299 element as a list, you need to look into how references work, because
3300 Perl will not magically convert between scalars and lists for you. See
3303 =item Scalar value @%s{%s} better written as $%s{%s}
3305 (W syntax) You've used a hash slice (indicated by @) to select a single
3306 element of a hash. Generally it's better to ask for a scalar value
3307 (indicated by $). The difference is that C<$foo{&bar}> always behaves
3308 like a scalar, both when assigning to it and when evaluating its
3309 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
3310 and provides a list context to its subscript, which can do weird things
3311 if you're expecting only one subscript.
3313 On the other hand, if you were actually hoping to treat the hash element
3314 as a list, you need to look into how references work, because Perl will
3315 not magically convert between scalars and lists for you. See
3318 =item Script is not setuid/setgid in suidperl
3320 (F) Oddly, the suidperl program was invoked on a script without a setuid
3321 or setgid bit set. This doesn't make much sense.
3323 =item Search pattern not terminated
3325 (F) The lexer couldn't find the final delimiter of a // or m{}
3326 construct. Remember that bracketing delimiters count nesting level.
3327 Missing the leading C<$> from a variable C<$m> may cause this error.
3329 Note that since Perl 5.9.0 a // can also be the I<defined-or>
3330 construct, not just the empty search pattern. Therefore code written
3331 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
3332 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
3334 =item %sseek() on unopened filehandle
3336 (W unopened) You tried to use the seek() or sysseek() function on a
3337 filehandle that was either never opened or has since been closed.
3339 =item select not implemented
3341 (F) This machine doesn't implement the select() system call.
3343 =item Self-ties of arrays and hashes are not supported
3345 (F) Self-ties are of arrays and hashes are not supported in
3346 the current implementation.
3348 =item Semicolon seems to be missing
3350 (W semicolon) A nearby syntax error was probably caused by a missing
3351 semicolon, or possibly some other missing operator, such as a comma.
3353 =item semi-panic: attempt to dup freed string
3355 (S internal) The internal newSVsv() routine was called to duplicate a
3356 scalar that had previously been marked as free.
3358 =item sem%s not implemented
3360 (F) You don't have System V semaphore IPC on your system.
3362 =item send() on closed socket %s
3364 (W closed) The socket you're sending to got itself closed sometime
3365 before now. Check your control flow.
3367 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
3369 (F) A regular expression ended with an incomplete extension (?. The <-- HERE
3370 shows in the regular expression about where the problem was discovered. See
3373 =item Sequence (?%s...) not implemented in regex; marked by <-- HERE in m/%s/
3375 (F) A proposed regular expression extension has the character reserved but
3376 has not yet been written. The <-- HERE shows in the regular expression about
3377 where the problem was discovered. See L<perlre>.
3379 =item Sequence (?%s...) not recognized in regex; marked by <-- HERE in m/%s/
3381 (F) You used a regular expression extension that doesn't make sense. The
3382 <-- HERE shows in the regular expression about where the problem was
3383 discovered. See L<perlre>.
3385 =item Sequence (?#... not terminated in regex; marked by <-- HERE in m/%s/
3387 (F) A regular expression comment must be terminated by a closing
3388 parenthesis. Embedded parentheses aren't allowed. The <-- HERE shows in
3389 the regular expression about where the problem was discovered. See
3392 =item Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/%s/
3394 (F) If the contents of a (?{...}) clause contains braces, they must balance
3395 for Perl to properly detect the end of the clause. The <-- HERE shows in
3396 the regular expression about where the problem was discovered. See
3399 =item 500 Server error
3405 This is the error message generally seen in a browser window when trying
3406 to run a CGI program (including SSI) over the web. The actual error text
3407 varies widely from server to server. The most frequently-seen variants
3408 are "500 Server error", "Method (something) not permitted", "Document
3409 contains no data", "Premature end of script headers", and "Did not
3410 produce a valid header".
3412 B<This is a CGI error, not a Perl error>.
3414 You need to make sure your script is executable, is accessible by the
3415 user CGI is running the script under (which is probably not the user
3416 account you tested it under), does not rely on any environment variables
3417 (like PATH) from the user it isn't running under, and isn't in a
3418 location where the CGI server can't find it, basically, more or less.
3419 Please see the following for more information:
3421 http://www.perl.org/CGI_MetaFAQ.html
3422 http://www.htmlhelp.org/faq/cgifaq.html
3423 http://www.w3.org/Security/Faq/
3425 You should also look at L<perlfaq9>.
3427 =item setegid() not implemented
3429 (F) You tried to assign to C<$)>, and your operating system doesn't
3430 support the setegid() system call (or equivalent), or at least Configure
3433 =item seteuid() not implemented
3435 (F) You tried to assign to C<< $> >>, and your operating system doesn't
3436 support the seteuid() system call (or equivalent), or at least Configure
3439 =item setpgrp can't take arguments
3441 (F) Your system has the setpgrp() from BSD 4.2, which takes no
3442 arguments, unlike POSIX setpgid(), which takes a process ID and process
3445 =item setrgid() not implemented
3447 (F) You tried to assign to C<$(>, and your operating system doesn't
3448 support the setrgid() system call (or equivalent), or at least Configure
3451 =item setruid() not implemented
3453 (F) You tried to assign to C<$<>, and your operating system doesn't
3454 support the setruid() system call (or equivalent), or at least Configure
3457 =item setsockopt() on closed socket %s
3459 (W closed) You tried to set a socket option on a closed socket. Did you
3460 forget to check the return value of your socket() call? See
3461 L<perlfunc/setsockopt>.
3463 =item Setuid/gid script is writable by world
3465 (F) The setuid emulator won't run a script that is writable by the
3466 world, because the world might have written on it already.
3468 =item shm%s not implemented
3470 (F) You don't have System V shared memory IPC on your system.
3472 =item !=~ should be !~
3474 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
3475 interpreted as the != (numeric not equal) and ~ (1's complement)
3476 operators: probably not what you intended.
3478 =item <> should be quotes
3480 (F) You wrote C<< require <file> >> when you should have written
3483 =item /%s/ should probably be written as "%s"
3485 (W syntax) You have used a pattern where Perl expected to find a string,
3486 as in the first argument to C<join>. Perl will treat the true or false
3487 result of matching the pattern against $_ as the string, which is
3488 probably not what you had in mind.
3490 =item shutdown() on closed socket %s
3492 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
3495 =item SIG%s handler "%s" not defined
3497 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
3498 Perhaps you put it into the wrong package?
3500 =item sort is now a reserved word
3502 (F) An ancient error message that almost nobody ever runs into anymore.
3503 But before sort was a keyword, people sometimes used it as a filehandle.
3505 =item Sort subroutine didn't return a numeric value
3507 (F) A sort comparison routine must return a number. You probably blew
3508 it by not using C<< <=> >> or C<cmp>, or by not using them correctly.
3509 See L<perlfunc/sort>.
3511 =item Sort subroutine didn't return single value
3513 (F) A sort comparison subroutine may not return a list value with more
3514 or less than one element. See L<perlfunc/sort>.
3516 =item splice() offset past end of array
3518 (W misc) You attempted to specify an offset that was past the end of
3519 the array passed to splice(). Splicing will instead commence at the end
3520 of the array, rather than past it. If this isn't what you want, try
3521 explicitly pre-extending the array by assigning $#array = $offset. See
3526 (P) The split was looping infinitely. (Obviously, a split shouldn't
3527 iterate more times than there are characters of input, which is what
3528 happened.) See L<perlfunc/split>.
3530 =item Statement unlikely to be reached
3532 (W exec) You did an exec() with some statement after it other than a
3533 die(). This is almost always an error, because exec() never returns
3534 unless there was a failure. You probably wanted to use system()
3535 instead, which does return. To suppress this warning, put the exec() in
3538 =item stat() on unopened filehandle %s
3540 (W unopened) You tried to use the stat() function on a filehandle that
3541 was either never opened or has since been closed.
3543 =item Stub found while resolving method `%s' overloading %s
3545 (P) Overloading resolution over @ISA tree may be broken by importation
3546 stubs. Stubs should never be implicitly created, but explicit calls to
3547 C<can> may break this.
3549 =item Subroutine %s redefined
3551 (W redefine) You redefined a subroutine. To suppress this warning, say
3554 no warnings 'redefine';
3555 eval "sub name { ... }";
3558 =item Substitution loop
3560 (P) The substitution was looping infinitely. (Obviously, a substitution
3561 shouldn't iterate more times than there are characters of input, which
3562 is what happened.) See the discussion of substitution in
3563 L<perlop/"Quote and Quote-like Operators">.
3565 =item Substitution pattern not terminated
3567 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
3568 construct. Remember that bracketing delimiters count nesting level.
3569 Missing the leading C<$> from variable C<$s> may cause this error.
3571 =item Substitution replacement not terminated
3573 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
3574 construct. Remember that bracketing delimiters count nesting level.
3575 Missing the leading C<$> from variable C<$s> may cause this error.
3577 =item substr outside of string
3579 (W substr),(F) You tried to reference a substr() that pointed outside of
3580 a string. That is, the absolute value of the offset was larger than the
3581 length of the string. See L<perlfunc/substr>. This warning is fatal if
3582 substr is used in an lvalue context (as the left hand side of an
3583 assignment or as a subroutine argument for example).
3585 =item suidperl is no longer needed since %s
3587 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but
3588 a version of the setuid emulator somehow got run anyway.
3590 =item Switch (?(condition)... contains too many branches in regex; marked by <-- HERE in m/%s/
3592 (F) A (?(condition)if-clause|else-clause) construct can have at most two
3593 branches (the if-clause and the else-clause). If you want one or both to
3594 contain alternation, such as using C<this|that|other>, enclose it in
3595 clustering parentheses:
3597 (?(condition)(?:this|that|other)|else-clause)
3599 The <-- HERE shows in the regular expression about where the problem was
3600 discovered. See L<perlre>.
3602 =item Switch condition not recognized in regex; marked by <-- HERE in m/%s/
3604 (F) If the argument to the (?(...)if-clause|else-clause) construct is a
3605 number, it can be only a number. The <-- HERE shows in the regular expression
3606 about where the problem was discovered. See L<perlre>.
3608 =item switching effective %s is not implemented
3610 (F) While under the C<use filetest> pragma, we cannot switch the real
3611 and effective uids or gids.
3615 (F) The final summary message when a C<perl -c> succeeds.
3619 (F) Probably means you had a syntax error. Common reasons include:
3621 A keyword is misspelled.
3622 A semicolon is missing.
3624 An opening or closing parenthesis is missing.
3625 An opening or closing brace is missing.
3626 A closing quote is missing.
3628 Often there will be another error message associated with the syntax
3629 error giving more information. (Sometimes it helps to turn on B<-w>.)
3630 The error message itself often tells you where it was in the line when
3631 it decided to give up. Sometimes the actual error is several tokens
3632 before this, because Perl is good at understanding random input.
3633 Occasionally the line number may be misleading, and once in a blue moon
3634 the only way to figure out what's triggering the error is to call
3635 C<perl -c> repeatedly, chopping away half the program each time to see
3636 if the error went away. Sort of the cybernetic version of S<20
3639 =item syntax error at line %d: `%s' unexpected
3641 (A) You've accidentally run your script through the Bourne shell instead
3642 of Perl. Check the #! line, or manually feed your script into Perl
3645 =item syntax error in file %s at line %d, next 2 tokens "%s"
3647 (F) This error is likely to occur if you run a perl5 script through
3648 a perl4 interpreter, especially if the next 2 tokens are "use strict"
3649 or "my $var" or "our $var".
3651 =item sysread() on closed filehandle %s
3653 (W closed) You tried to read from a closed filehandle.
3655 =item sysread() on unopened filehandle %s
3657 (W unopened) You tried to read from a filehandle that was never opened.
3659 =item System V %s is not implemented on this machine
3661 (F) You tried to do something with a function beginning with "sem",
3662 "shm", or "msg" but that System V IPC is not implemented in your
3663 machine. In some machines the functionality can exist but be
3664 unconfigured. Consult your system support.
3666 =item syswrite() on closed filehandle %s
3668 (W closed) The filehandle you're writing to got itself closed sometime
3669 before now. Check your control flow.
3671 =item C<-T> and C<-B> not implemented on filehandles
3673 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
3674 know about your kind of stdio. You'll have to use a filename instead.
3676 =item Target of goto is too deeply nested
3678 (F) You tried to use C<goto> to reach a label that was too deeply nested
3679 for Perl to reach. Perl is doing you a favor by refusing.
3681 =item tell() on unopened filehandle
3683 (W unopened) You tried to use the tell() function on a filehandle that
3684 was either never opened or has since been closed.
3686 =item That use of $[ is unsupported
3688 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
3689 as a compiler directive. You may say only one of
3698 This is to prevent the problem of one module changing the array base out
3699 from under another module inadvertently. See L<perlvar/$[>.
3701 =item The crypt() function is unimplemented due to excessive paranoia
3703 (F) Configure couldn't find the crypt() function on your machine,
3704 probably because your vendor didn't supply it, probably because they
3705 think the U.S. Government thinks it's a secret, or at least that they
3706 will continue to pretend that it is. And if you quote me on that, I
3709 =item The %s function is unimplemented
3711 The function indicated isn't implemented on this architecture, according
3712 to the probings of Configure.
3714 =item The stat preceding %s wasn't an lstat
3716 (F) It makes no sense to test the current stat buffer for symbolic
3717 linkhood if the last stat that wrote to the stat buffer already went
3718 past the symlink to get to the real file. Use an actual filename
3721 =item The 'unique' attribute may only be applied to 'our' variables
3723 (F) Currently this attribute is not supported on C<my> or C<sub>
3724 declarations. See L<perlfunc/our>.
3726 =item This Perl can't reset CRTL environ elements (%s)
3728 =item This Perl can't set CRTL environ elements (%s=%s)
3730 (W internal) Warnings peculiar to VMS. You tried to change or delete an
3731 element of the CRTL's internal environ array, but your copy of Perl
3732 wasn't built with a CRTL that contained the setenv() function. You'll
3733 need to rebuild Perl with a CRTL that does, or redefine
3734 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
3735 target of the change to
3736 %ENV which produced the warning.
3738 =item thread failed to start: %s
3740 (F) The entry point function of threads->create() failed for some reason.
3742 =item Tied variable freed while still in use
3744 (F) An access method for a tied variable (e.g. FETCH) did something to
3745 free the variable. Since continuing the current operation is likely
3746 to result in a coredump, Perl is bailing out instead.
3748 =item times not implemented
3750 (F) Your version of the C library apparently doesn't do times(). I
3751 suspect you're not running on Unix.
3753 =item To%s: illegal mapping '%s'
3755 (F) You tried to define a customized To-mapping for lc(), lcfirst,
3756 uc(), or ucfirst() (or their string-inlined versions), but you
3757 specified an illegal mapping.
3758 See L<perlunicode/"User-Defined Character Properties">.
3760 =item Too deeply nested ()-groups
3762 (F) Your template contains ()-groups with a ridiculously deep nesting level.
3764 =item Too few args to syscall
3766 (F) There has to be at least one argument to syscall() to specify the
3767 system call to call, silly dilly.
3769 =item Too late for "-%s" option
3771 (X) The #! line (or local equivalent) in a Perl script contains the
3772 B<-M> or B<-m> option. This is an error because B<-M> and B<-m> options
3773 are not intended for use inside scripts. Use the C<use> pragma instead.
3775 =item Too late for "B<-T>" option
3777 (X) The #! line (or local equivalent) in a Perl script contains the
3778 B<-T> option, but Perl was not invoked with B<-T> in its command line.
3779 This is an error because, by the time Perl discovers a B<-T> in a
3780 script, it's too late to properly taint everything from the environment.
3783 If the Perl script is being executed as a command using the #!
3784 mechanism (or its local equivalent), this error can usually be fixed by
3785 editing the #! line so that the B<-T> option is a part of Perl's first
3786 argument: e.g. change C<perl -n -T> to C<perl -T -n>.
3788 If the Perl script is being executed as C<perl scriptname>, then the
3789 B<-T> option must appear on the command line: C<perl -T scriptname>.
3791 =item Too late to run %s block
3793 (W void) A CHECK or INIT block is being defined during run time proper,
3794 when the opportunity to run them has already passed. Perhaps you are
3795 loading a file with C<require> or C<do> when you should be using C<use>
3796 instead. Or perhaps you should put the C<require> or C<do> inside a
3799 =item Too many args to syscall
3801 (F) Perl supports a maximum of only 14 args to syscall().
3803 =item Too many arguments for %s
3805 (F) The function requires fewer arguments than you specified.
3809 (A) You've accidentally run your script through B<csh> instead of Perl.
3810 Check the #! line, or manually feed your script into Perl yourself.
3814 (A) You've accidentally run your script through B<csh> instead of Perl.
3815 Check the #! line, or manually feed your script into Perl yourself.
3817 =item Trailing \ in regex m/%s/
3819 (F) The regular expression ends with an unbackslashed backslash.
3820 Backslash it. See L<perlre>.
3822 =item Transliteration pattern not terminated
3824 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
3825 or y/// or y[][] construct. Missing the leading C<$> from variables
3826 C<$tr> or C<$y> may cause this error.
3828 =item Transliteration replacement not terminated
3830 (F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
3833 =item '%s' trapped by operation mask
3835 (F) You tried to use an operator from a Safe compartment in which it's
3836 disallowed. See L<Safe>.
3838 =item truncate not implemented
3840 (F) Your machine doesn't implement a file truncation mechanism that
3841 Configure knows about.
3843 =item Type of arg %d to %s must be %s (not %s)
3845 (F) This function requires the argument in that position to be of a
3846 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
3847 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
3848 {EXPR} forms as an explicit dereference. See L<perlref>.
3850 =item umask not implemented
3852 (F) Your machine doesn't implement the umask function and you tried to
3853 use it to restrict permissions for yourself (EXPR & 0700).
3855 =item Unable to create sub named "%s"
3857 (F) You attempted to create or access a subroutine with an illegal name.
3859 =item Unbalanced context: %d more PUSHes than POPs
3861 (W internal) The exit code detected an internal inconsistency in how
3862 many execution contexts were entered and left.
3864 =item Unbalanced saves: %d more saves than restores
3866 (W internal) The exit code detected an internal inconsistency in how
3867 many values were temporarily localized.
3869 =item Unbalanced scopes: %d more ENTERs than LEAVEs
3871 (W internal) The exit code detected an internal inconsistency in how
3872 many blocks were entered and left.
3874 =item Unbalanced tmps: %d more allocs than frees
3876 (W internal) The exit code detected an internal inconsistency in how
3877 many mortal scalars were allocated and freed.
3879 =item Undefined format "%s" called
3881 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3882 another package? See L<perlform>.
3884 =item Undefined sort subroutine "%s" called
3886 (F) The sort comparison routine specified doesn't seem to exist.
3887 Perhaps it's in a different package? See L<perlfunc/sort>.
3889 =item Undefined subroutine &%s called
3891 (F) The subroutine indicated hasn't been defined, or if it was, it has
3892 since been undefined.
3894 =item Undefined subroutine called
3896 (F) The anonymous subroutine you're trying to call hasn't been defined,
3897 or if it was, it has since been undefined.
3899 =item Undefined subroutine in sort
3901 (F) The sort comparison routine specified is declared but doesn't seem
3902 to have been defined yet. See L<perlfunc/sort>.
3904 =item Undefined top format "%s" called
3906 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3907 another package? See L<perlform>.
3909 =item Undefined value assigned to typeglob
3911 (W misc) An undefined value was assigned to a typeglob, a la
3912 C<*foo = undef>. This does nothing. It's possible that you really mean
3915 =item %s: Undefined variable
3917 (A) You've accidentally run your script through B<csh> instead of Perl.
3918 Check the #! line, or manually feed your script into Perl yourself.
3920 =item unexec of %s into %s failed!
3922 (F) The unexec() routine failed for some reason. See your local FSF
3923 representative, who probably put it there in the first place.
3925 =item Unicode character %s is illegal
3927 (W utf8) Certain Unicode characters have been designated off-limits by
3928 the Unicode standard and should not be generated. If you really know
3929 what you are doing you can turn off this warning by C<no warnings 'utf8';>.
3931 =item Unknown BYTEORDER
3933 (F) There are no byte-swapping functions for a machine with this byte
3936 =item Unknown open() mode '%s'
3938 (F) The second argument of 3-argument open() is not among the list
3939 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
3940 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
3942 =item Unknown PerlIO layer "%s"
3944 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
3945 system. (Layers take care of transforming data between external and
3946 internal representations.) Note that some layers, such as C<mmap>,
3947 are not supported in all environments. If your program didn't
3948 explicitly request the failing operation, it may be the result of the
3949 value of the environment variable PERLIO.
3951 =item Unknown process %x sent message to prime_env_iter: %s
3953 (P) An error peculiar to VMS. Perl was reading values for %ENV before
3954 iterating over it, and someone else stuck a message in the stream of
3955 data Perl expected. Someone's very confused, or perhaps trying to
3956 subvert Perl's population of %ENV for nefarious purposes.
3958 =item Unknown "re" subpragma '%s' (known ones are: %s)
3960 You tried to use an unknown subpragma of the "re" pragma.
3962 =item Unknown switch condition (?(%.2s in regex; marked by <-- HERE in m/%s/
3964 (F) The condition part of a (?(condition)if-clause|else-clause) construct
3965 is not known. The condition may be lookahead or lookbehind (the condition
3966 is true if the lookahead or lookbehind is true), a (?{...}) construct (the
3967 condition is true if the code evaluates to a true value), or a number (the
3968 condition is true if the set of capturing parentheses named by the number
3971 The <-- HERE shows in the regular expression about where the problem was
3972 discovered. See L<perlre>.
3974 =item Unknown Unicode option letter '%c'
3976 You specified an unknown Unicode option. See L<perlrun> documentation
3977 of the C<-C> switch for the list of known options.
3979 =item Unknown Unicode option value %x
3981 You specified an unknown Unicode option. See L<perlrun> documentation
3982 of the C<-C> switch for the list of known options.
3984 =item Unknown warnings category '%s'
3986 (F) An error issued by the C<warnings> pragma. You specified a warnings
3987 category that is unknown to perl at this point.
3989 Note that if you want to enable a warnings category registered by a module
3990 (e.g. C<use warnings 'File::Find'>), you must have imported this module
3993 =item unmatched [ in regex; marked by <-- HERE in m/%s/
3995 (F) The brackets around a character class must match. If you wish to
3996 include a closing bracket in a character class, backslash it or put it
3997 first. The <-- HERE shows in the regular expression about where the problem
3998 was discovered. See L<perlre>.
4000 =item unmatched ( in regex; marked by <-- HERE in m/%s/
4002 (F) Unbackslashed parentheses must always be balanced in regular
4003 expressions. If you're a vi user, the % key is valuable for finding the
4004 matching parenthesis. The <-- HERE shows in the regular expression about
4005 where the problem was discovered. See L<perlre>.
4007 =item Unmatched right %s bracket
4009 (F) The lexer counted more closing curly or square brackets than opening
4010 ones, so you're probably missing a matching opening bracket. As a
4011 general rule, you'll find the missing one (so to speak) near the place
4012 you were last editing.
4014 =item Unquoted string "%s" may clash with future reserved word
4016 (W reserved) You used a bareword that might someday be claimed as a
4017 reserved word. It's best to put such a word in quotes, or capitalize it
4018 somehow, or insert an underbar into it. You might also declare it as a
4021 =item Unrecognized character %s
4023 (F) The Perl parser has no idea what to do with the specified character
4024 in your Perl script (or eval). Perhaps you tried to run a compressed
4025 script, a binary program, or a directory as a Perl program.
4027 =item /%s/: Unrecognized escape \\%c in character class passed through
4029 (W regexp) You used a backslash-character combination which is not
4030 recognized by Perl inside character classes. The character was
4031 understood literally.
4033 =item Unrecognized escape \\%c passed through
4035 (W misc) You used a backslash-character combination which is not
4038 =item Unrecognized escape \\%c passed through in regex; marked by <-- HERE in m/%s/
4040 (W regexp) You used a backslash-character combination which is not
4041 recognized by Perl. This combination appears in an interpolated variable or
4042 a C<'>-delimited regular expression. The character was understood
4043 literally. The <-- HERE shows in the regular expression about where the
4044 escape was discovered.
4046 =item Unrecognized signal name "%s"
4048 (F) You specified a signal name to the kill() function that was not
4049 recognized. Say C<kill -l> in your shell to see the valid signal names
4052 =item Unrecognized switch: -%s (-h will show valid options)
4054 (F) You specified an illegal option to Perl. Don't do that. (If you
4055 think you didn't do that, check the #! line to see if it's supplying the
4056 bad switch on your behalf.)
4058 =item Unsuccessful %s on filename containing newline
4060 (W newline) A file operation was attempted on a filename, and that
4061 operation failed, PROBABLY because the filename contained a newline,
4062 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
4064 =item Unsupported directory function "%s" called
4066 (F) Your machine doesn't support opendir() and readdir().
4068 =item Unsupported function %s
4070 (F) This machine doesn't implement the indicated function, apparently.
4071 At least, Configure doesn't think so.
4073 =item Unsupported function fork
4075 (F) Your version of executable does not support forking.
4077 Note that under some systems, like OS/2, there may be different flavors
4078 of Perl executables, some of which may support fork, some not. Try
4079 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
4081 =item Unsupported script encoding
4083 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
4084 declares it to be in a Unicode encoding that Perl cannot yet read.
4086 =item Unsupported socket function "%s" called
4088 (F) Your machine doesn't support the Berkeley socket mechanism, or at
4089 least that's what Configure thought.
4091 =item Unterminated attribute list
4093 (F) The lexer found something other than a simple identifier at the
4094 start of an attribute, and it wasn't a semicolon or the start of a
4095 block. Perhaps you terminated the parameter list of the previous
4096 attribute too soon. See L<attributes>.
4098 =item Unterminated attribute parameter in attribute list
4100 (F) The lexer saw an opening (left) parenthesis character while parsing
4101 an attribute list, but the matching closing (right) parenthesis
4102 character was not found. You may need to add (or remove) a backslash
4103 character to get your parentheses to balance. See L<attributes>.
4105 =item Unterminated compressed integer
4107 (F) An argument to unpack("w",...) was incompatible with the BER
4108 compressed integer format and could not be converted to an integer.
4109 See L<perlfunc/pack>.
4111 =item Unterminated <> operator
4113 (F) The lexer saw a left angle bracket in a place where it was expecting
4114 a term, so it's looking for the corresponding right angle bracket, and
4115 not finding it. Chances are you left some needed parentheses out
4116 earlier in the line, and you really meant a "less than".
4118 =item untie attempted while %d inner references still exist
4120 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
4121 still valid when C<untie> was called.
4123 =item Usage: POSIX::%s(%s)
4125 (F) You called a POSIX function with incorrect arguments.
4126 See L<POSIX/FUNCTIONS> for more information.
4128 =item Usage: Win32::%s(%s)
4130 (F) You called a Win32 function with incorrect arguments.
4131 See L<Win32> for more information.
4133 =item Useless (?-%s) - don't use /%s modifier in regex; marked by <-- HERE in m/%s/
4135 (W regexp) You have used an internal modifier such as (?-o) that has no
4136 meaning unless removed from the entire regexp:
4138 if ($string =~ /(?-o)$pattern/o) { ... }
4142 if ($string =~ /$pattern/) { ... }
4144 The <-- HERE shows in the regular expression about
4145 where the problem was discovered. See L<perlre>.
4147 =item Useless localization of %s
4149 (W syntax) The localization of lvalues such as C<local($x=10)> is
4150 legal, but in fact the local() currently has no effect. This may change at
4151 some point in the future, but in the meantime such code is discouraged.
4153 =item Useless (?%s) - use /%s modifier in regex; marked by <-- HERE in m/%s/
4155 (W regexp) You have used an internal modifier such as (?o) that has no
4156 meaning unless applied to the entire regexp:
4158 if ($string =~ /(?o)$pattern/) { ... }
4162 if ($string =~ /$pattern/o) { ... }
4164 The <-- HERE shows in the regular expression about
4165 where the problem was discovered. See L<perlre>.
4167 =item Useless use of %s in void context
4169 (W void) You did something without a side effect in a context that does
4170 nothing with the return value, such as a statement that doesn't return a
4171 value from a block, or the left side of a scalar comma operator. Very
4172 often this points not to stupidity on your part, but a failure of Perl
4173 to parse your program the way you thought it would. For example, you'd
4174 get this if you mixed up your C precedence with Python precedence and
4179 when you meant to say
4181 ($one, $two) = (1, 2);
4183 Another common error is to use ordinary parentheses to construct a list
4184 reference when you should be using square or curly brackets, for
4189 when you should have said
4193 The square brackets explicitly turn a list value into a scalar value,
4194 while parentheses do not. So when a parenthesized list is evaluated in
4195 a scalar context, the comma is treated like C's comma operator, which
4196 throws away the left argument, which is not what you want. See
4197 L<perlref> for more on this.
4199 This warning will not be issued for numerical constants equal to 0 or 1
4200 since they are often used in statements like
4202 1 while sub_with_side_effects() ;
4204 String constants that would normally evaluate to 0 or 1 are warned
4207 =item Useless use of "re" pragma
4209 (W) You did C<use re;> without any arguments. That isn't very useful.
4211 =item Useless use of sort in scalar context
4213 (W void) You used sort in scalar context, as in :
4217 This is not very useful, and perl currently optimizes this away.
4219 =item Useless use of %s with no values
4221 (W syntax) You used the push() or unshift() function with no arguments
4222 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
4223 usually have any effect on the array, so is completely useless. It's
4224 possible in principle that push(@tied_array) could have some effect
4225 if the array is tied to a class which implements a PUSH method. If so,
4226 you can write it as C<push(@tied_array,())> to avoid this warning.
4228 =item "use" not allowed in expression
4230 (F) The "use" keyword is recognized and executed at compile time, and
4231 returns no useful value. See L<perlmod>.
4233 =item Use of bare << to mean <<"" is deprecated
4235 (D deprecated) You are now encouraged to use the explicitly quoted form
4236 if you wish to use an empty line as the terminator of the here-document.
4238 =item Use of chdir('') or chdir(undef) as chdir() deprecated
4240 (D deprecated) chdir() with no arguments is documented to change to
4241 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
4242 behavior, but that has been deprecated. In future versions they
4245 Be careful to check that what you pass to chdir() is defined and not
4246 blank, else you might find yourself in your home directory.
4248 =item Use of /c modifier is meaningless in s///
4250 (W regexp) You used the /c modifier in a substitution. The /c
4251 modifier is not presently meaningful in substitutions.
4253 =item Use of /c modifier is meaningless without /g
4255 (W regexp) You used the /c modifier with a regex operand, but didn't
4256 use the /g modifier. Currently, /c is meaningful only when /g is
4257 used. (This may change in the future.)
4259 =item Use of freed value in iteration
4261 (F) Perhaps you modified the iterated array within the loop?
4262 This error is typically caused by code like the following:
4265 @a = () for (1,2,@a);
4267 You are not supposed to modify arrays while they are being iterated over.
4268 For speed and efficiency reasons, Perl internally does not do full
4269 reference-counting of iterated items, hence deleting such an item in the
4270 middle of an iteration causes Perl to see a freed value.
4272 =item Use of *glob{FILEHANDLE} is deprecated
4274 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
4275 to access the filehandle slot within a typeglob.
4277 =item Use of /g modifier is meaningless in split
4279 (W regexp) You used the /g modifier on the pattern for a C<split>
4280 operator. Since C<split> always tries to match the pattern
4281 repeatedly, the C</g> has no effect.
4283 =item Use of implicit split to @_ is deprecated
4285 (D deprecated) It makes a lot of work for the compiler when you clobber
4286 a subroutine's argument list, so it's better if you assign the results
4287 of a split() explicitly to an array (or list).
4289 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
4291 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD> subroutines
4292 are looked up as methods (using the C<@ISA> hierarchy) even when the
4293 subroutines to be autoloaded were called as plain functions (e.g.
4294 C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or C<<
4297 This bug will be rectified in future by using method lookup only for
4298 methods' C<AUTOLOAD>s. However, there is a significant base of existing
4299 code that may be using the old behavior. So, as an interim step, Perl
4300 currently issues an optional warning when non-methods use inherited
4303 The simple rule is: Inheritance will not work when autoloading
4304 non-methods. The simple fix for old code is: In any module that used
4305 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
4306 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
4309 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
4310 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
4311 C<use AutoLoader 'AUTOLOAD';>.
4313 =item Use of %s in printf format not supported
4315 (F) You attempted to use a feature of printf that is accessible from
4316 only C. This usually means there's a better way to do it in Perl.
4318 =item Use of $# is deprecated
4320 (D deprecated) This was an ill-advised attempt to emulate a poorly
4321 defined B<awk> feature. Use an explicit printf() or sprintf() instead.
4323 =item Use of %s is deprecated
4325 (D deprecated) The construct indicated is no longer recommended for use,
4326 generally because there's a better way to do it, and also because the
4327 old way has bad side effects.
4329 =item Use of -l on filehandle %s
4331 (W io) A filehandle represents an opened file, and when you opened the file
4332 it already went past any symlink you are presumably trying to look for.
4333 The operation returned C<undef>. Use a filename instead.
4335 =item Deprecated use of my() in false conditional
4337 (D deprecated) You used a declaration similar to C<my $x if 0>.
4338 There has been a long-standing bug in Perl that causes a lexical variable
4339 not to be cleared at scope exit when its declaration includes a false
4340 conditional. Some people have exploited this bug to achieve a kind of
4341 static variable. Since we intend to fix this bug, we don't want people
4342 relying on this behavior. You can achieve a similar static effect by
4343 declaring the variable in a separate block outside the function, eg
4345 sub f { my $x if 0; return $x++ }
4349 { my $x; sub f { return $x++ } }
4351 =item Use of "package" with no arguments is deprecated
4353 (D deprecated) You used the C<package> keyword without specifying a package
4354 name. So no namespace is current at all. Using this can cause many
4355 otherwise reasonable constructs to fail in baffling ways. C<use strict;>
4358 =item Use of reference "%s" as array index
4360 (W misc) You tried to use a reference as an array index; this probably
4361 isn't what you mean, because references in numerical context tend
4362 to be huge numbers, and so usually indicates programmer error.
4364 If you really do mean it, explicitly numify your reference, like so:
4365 C<$array[0+$ref]>. This warning is not given for overloaded objects,
4366 either, because you can overload the numification and stringification
4367 operators and then you assumedly know what you are doing.
4369 =item Use of reserved word "%s" is deprecated
4371 (D deprecated) The indicated bareword is a reserved word. Future
4372 versions of perl may use it as a keyword, so you're better off either
4373 explicitly quoting the word in a manner appropriate for its context of
4374 use, or using a different name altogether. The warning can be
4375 suppressed for subroutine names by either adding a C<&> prefix, or using
4376 a package qualifier, e.g. C<&our()>, or C<Foo::our()>.
4378 =item Use of tainted arguments in %s is deprecated
4380 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
4381 arguments and at least one of them is tainted. This used to be allowed
4382 but will become a fatal error in a future version of perl. Untaint your
4383 arguments. See L<perlsec>.
4385 =item Use of uninitialized value%s
4387 (W uninitialized) An undefined value was used as if it were already
4388 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
4389 To suppress this warning assign a defined value to your variables.
4391 To help you figure out what was undefined, perl tells you what operation
4392 you used the undefined value in. Note, however, that perl optimizes your
4393 program and the operation displayed in the warning may not necessarily
4394 appear literally in your program. For example, C<"that $foo"> is
4395 usually optimized into C<"that " . $foo>, and the warning will refer to
4396 the C<concatenation (.)> operator, even though there is no C<.> in your
4399 =item Using a hash as a reference is deprecated
4401 (D deprecated) You tried to use a hash as a reference, as in
4402 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
4403 used to allow this syntax, but shouldn't have. It is now deprecated, and will
4404 be removed in a future version.
4406 =item Using an array as a reference is deprecated
4408 (D deprecated) You tried to use an array as a reference, as in
4409 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
4410 allow this syntax, but shouldn't have. It is now deprecated, and will be
4411 removed in a future version.
4413 =item UTF-16 surrogate %s
4415 (W utf8) You tried to generate half of an UTF-16 surrogate by
4416 requesting a Unicode character between the code points 0xD800 and
4417 0xDFFF (inclusive). That range is reserved exclusively for the use of
4418 UTF-16 encoding (by having two 16-bit UCS-2 characters); but Perl
4419 encodes its characters in UTF-8, so what you got is a very illegal
4420 character. If you really know what you are doing you can turn off
4421 this warning by C<no warnings 'utf8';>.
4423 =item Value of %s can be "0"; test with defined()
4425 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
4426 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
4427 can return a value of "0"; that would make the conditional expression
4428 false, which is probably not what you intended. When using these
4429 constructs in conditional expressions, test their values with the
4430 C<defined> operator.
4432 =item Value of CLI symbol "%s" too long
4434 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
4435 %ENV element from a CLI symbol table, and found a resultant string
4436 longer than 1024 characters. The return value has been truncated to
4439 =item Variable "%s" is not available
4441 (W closure) During compilation, an inner named subroutine or eval is
4442 attempting to capture an outer lexical that is not currently available.
4443 This can happen for one of two reasons. First, the outer lexical may be
4444 declared in an outer anonymous subroutine that has not yet been created.
4445 (Remember that named subs are created at compile time, while anonymous
4446 subs are created at run-time.) For example,
4448 sub { my $a; sub f { $a } }
4450 At the time that f is created, it can't capture the current value of $a,
4451 since the anonymous subroutine hasn't been created yet. Conversely,
4452 the following won't give a warning since the anonymous subroutine has by
4453 now been created and is live:
4455 sub { my $a; eval 'sub f { $a }' }->();
4457 The second situation is caused by an eval accessing a variable that has
4458 gone out of scope, for example,
4466 Here, when the '$a' in the eval is being compiled, f() is not currently being
4467 executed, so its $a is not available for capture.
4469 =item Variable "%s" is not imported%s
4471 (F) While "use strict" in effect, you referred to a global variable that
4472 you apparently thought was imported from another module, because
4473 something else of the same name (usually a subroutine) is exported by
4474 that module. It usually means you put the wrong funny character on the
4475 front of your variable.
4477 =item Variable length lookbehind not implemented in regex; marked by <-- HERE in m/%s/
4479 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
4480 known at compile time. The <-- HERE shows in the regular expression about
4481 where the problem was discovered. See L<perlre>.
4483 =item "%s" variable %s masks earlier declaration in same %s
4485 (W misc) A "my" or "our" variable has been redeclared in the current
4486 scope or statement, effectively eliminating all access to the previous
4487 instance. This is almost always a typographical error. Note that the
4488 earlier variable will still exist until the end of the scope or until
4489 all closure referents to it are destroyed.
4491 =item Variable syntax
4493 (A) You've accidentally run your script through B<csh> instead
4494 of Perl. Check the #! line, or manually feed your script into
4497 =item Variable "%s" will not stay shared
4499 (W closure) An inner (nested) I<named> subroutine is referencing a
4500 lexical variable defined in an outer named subroutine.
4502 When the inner subroutine is called, it will see the value of
4503 the outer subroutine's variable as it was before and during the *first*
4504 call to the outer subroutine; in this case, after the first call to the
4505 outer subroutine is complete, the inner and outer subroutines will no
4506 longer share a common value for the variable. In other words, the
4507 variable will no longer be shared.
4509 This problem can usually be solved by making the inner subroutine
4510 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
4511 reference variables in outer subroutines are created, they
4512 are automatically rebound to the current values of such variables.
4514 =item Version number must be a constant number
4516 (P) The attempt to translate a C<use Module n.n LIST> statement into
4517 its equivalent C<BEGIN> block found an internal inconsistency with
4520 =item v-string in use/require is non-portable
4522 (W portable) The use of v-strings is non-portable to older, pre-5.6, Perls.
4523 If you want your scripts to be backward portable, use the floating
4524 point version number: for example, instead of C<use 5.6.1> say
4525 C<use 5.006_001>. This of course won't help: the older Perls
4526 won't suddenly start understanding newer features, but at least
4527 they will show a sensible error message indicating the required
4530 =item Warning: something's wrong
4532 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
4533 you called it with no args and C<$_> was empty.
4535 =item Warning: unable to close filehandle %s properly
4537 (S) The implicit close() done by an open() got an error indication on
4538 the close(). This usually indicates your file system ran out of disk
4541 =item Warning: Use of "%s" without parentheses is ambiguous
4543 (S ambiguous) You wrote a unary operator followed by something that
4544 looks like a binary operator that could also have been interpreted as a
4545 term or unary operator. For instance, if you know that the rand
4546 function has a default argument of 1.0, and you write
4550 you may THINK you wrote the same thing as
4554 but in actual fact, you got
4558 So put in parentheses to say what you really mean.
4560 =item Wide character in %s
4562 (W utf8) Perl met a wide character (>255) when it wasn't expecting
4563 one. This warning is by default on for I/O (like print). The easiest
4564 way to quiet this warning is simply to add the C<:utf8> layer to the
4565 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
4566 warning is to add C<no warnings 'utf8';> but that is often closer to
4567 cheating. In general, you are supposed to explicitly mark the
4568 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
4570 =item Within []-length '%c' not allowed
4572 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]> only if
4573 C<TEMPLATE> always matches the same amount of packed bytes that can be
4574 determined from the template alone. This is not possible if it contains an
4575 of the codes @, /, U, u, w or a *-length. Redesign the template.
4577 =item write() on closed filehandle %s
4579 (W closed) The filehandle you're writing to got itself closed sometime
4580 before now. Check your control flow.
4582 =item %s "\x%s" does not map to Unicode
4584 When reading in different encodings Perl tries to map everything
4585 into Unicode characters. The bytes you read in are not legal in
4586 this encoding, for example
4588 utf8 "\xE4" does not map to Unicode
4590 if you try to read in the a-diaereses Latin-1 as UTF-8.
4592 =item 'X' outside of string
4594 (F) You had a (un)pack template that specified a relative position before
4595 the beginning of the string being (un)packed. See L<perlfunc/pack>.
4597 =item 'x' outside of string in unpack
4599 (F) You had a pack template that specified a relative position after
4600 the end of the string being unpacked. See L<perlfunc/pack>.
4602 =item Xsub "%s" called in sort
4604 (F) The use of an external subroutine as a sort comparison is not yet
4607 =item Xsub called in sort
4609 (F) The use of an external subroutine as a sort comparison is not yet
4612 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
4614 (F) And you probably never will, because you probably don't have the
4615 sources to your kernel, and your vendor probably doesn't give a rip
4616 about what you want. Your best bet is to put a setuid C wrapper around
4619 =item You need to quote "%s"
4621 (W syntax) You assigned a bareword as a signal handler name.
4622 Unfortunately, you already have a subroutine of that name declared,
4623 which means that Perl 5 will try to call the subroutine when the
4624 assignment is executed, which is probably not what you want. (If it IS
4625 what you want, put an & in front.)
4627 =item Your random numbers are not that random
4629 (F) When trying to initialise the random seed for hashes, Perl could
4630 not get any randomness out of your system. This usually indicates
4631 Something Very Wrong.